2019--2020学年度第二学期重点班周测5

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2020人教版三年级数学下第五单元测试卷含答案4套

2020春人教版三年级数学下册五单元测试卷4套2019-2020学年度第二学期三年级数学下册第五单元测试卷（一）一、填一填。

（每空1分，共20分）1.常用的面积单位有（）、（）和（）o2.在括号里填上合适的单位名称。

一块手伯的面积约是500（）一张银行卡的面积缠40（）一间卧室的面积约影（）一台电脑的屏幕的面积约敝）旗杆的高度约为10（）铅笔长约15（）3.一个长方形的面积是64平方分米，它的宽是4分米，长是（）分米。

4.一个长方形，於8米，宽17米，它的面积是）,周长埴）。

5.一个正方形的周长是64米，它的面积是（）。

6.一张正方形餐桌，它的边长是14分米，半张餐桌的面积是（）平方分米。

7.900平方分米=（）平方米7000平方厘米=（）平方分米600厘米=（）分米8平方分米=（）平方厘米8.下面两个图形的面积分别是多少？（每个口代表1平方厘米）图形①的面积是（）平方厘米。

图形②的面积是（）平方厘米。

二、辨一辨。

（对的画“寸'，错的画"X”）（每题1分,共5分）1.面积相等的长方形，它们的周长也相等。

（）2.边长是4厘米的正方形的周长和面积相等。

（）3.面积是1平方米的正方形的边长是1000厘米。

（）4.8厘米比6平方厘米大。

（）5.面积是36平方米的长方形有若干个，但面积是36平方米的正方形却只有一个。

（）三、选一选。

（把正确答案的序号填在括号里）（每题2分，共10分）1.下面图形中，面积最小的是（）（1个小方格表示1平方厘米）。

2.下面（）的面积接近1平方分米。

A.指甲B.大门C.粉笔盒的底面3.用同样长的两根铁丝分别围成一个长方形和一个正方形，它们的面积相比较，（）oA.同样大B,长方形的面积大C.正方形的面积大4.实验二小的操场占地大约（）平方米。

A.90B.9000C.9005.用8个边长是1分米的正方形拼成的长方形的面积是（）平方分米。

A.16B.8C.64四、我会按要求解答。

福建省泉州市2019-2020学年中考第二次质量检测数学试题含解析

福建省泉州市2019-2020学年中考第二次质量检测数学试题一、选择题（本大题共12个小题，每小题4分，共48分．在每小题给出的四个选项中，只有一项是符合题目要求的．）1．有理数a、b在数轴上的位置如图所示，则下列结论中正确的是（）A．a+b＞0 B．ab＞0 C．a﹣b＜o D．a÷b＞02．已知抛物线y＝x2+（2a+1）x+a2﹣a，则抛物线的顶点不可能在（）A．第一象限B．第二象限C．第三象限D．第四象限3．如果一组数据1、2、x、5、6的众数是6，则这组数据的中位数是（）A．1 B．2 C．5 D．64．汽车刹车后行驶的距离s（单位：m）关于行驶的时间t（单位：s）的函数解析式是s=20t﹣5t2，汽车刹车后停下来前进的距离是（）A．10m B．20m C．30m D．40m5．一条数学信息在一周内被转发了2180000次，将数据2180000用科学记数法表示为（）A．2.18×106B．2.18×105C．21.8×106D．21.8×1056．如图，△ABC中AB两个顶点在x轴的上方，点C的坐标是（﹣1，0），以点C为位似中心，在x轴的下方作△ABC的位似图形△A′B′C′，且△A′B′C′与△ABC的位似比为2：1．设点B的对应点B′的横坐标是a，则点B的横坐标是（）A．12a-B．1(1)2a-+C．1(1)2a--D．1(3)2a-+7．在0，π，﹣3，0.6，2这5个实数中，无理数的个数为（）A．1个B．2个C．3个D．4个8．估计10﹣1的值在（）A．1和2之间B．2和3之间C．3和4之间D．4和5之间9．如图，在△ABC中，∠ACB＝90°，沿CD折叠△CBD，使点B恰好落在AC边上的点E处．若∠A ＝24°，则∠BDC的度数为()A．42°B．66°C．69°D．77°10．在平面直角坐标系中，正方形A1B1C1D1、D1 E1E2B2、A2B2 C2D2、D2E3E4B3…按如图所示的方式放置，其中点B1在y轴上，点C1、E1、E2、C2、E3、E4、C3…在x轴上，已知正方形A1B1C1D1的边长为l，∠B1C1O=60°，B1C1∥B2C2∥B3C3…，则正方形A2017B2017C2017 D2017的边长是（）A．（）2016B．（）2017C．（）2016D．（）201711．目前，世界上能制造出的最小晶体管的长度只有0.000 000 04m，将0.000 000 04用科学记数法表示为（）A．0.4×108B．4×108C．4×10﹣8D．﹣4×10812．长度单位1纳米米，目前发现一种新型病毒直径为25100纳米，用科学记数法表示该病毒直径是（）A．米B．米C．米D．米二、填空题：（本大题共6个小题，每小题4分，共24分．）13．在平面直角坐标系中，点A的坐标是(-1,2) .作点A关于x 轴的对称点，得到点A1，再将点A1向下平移4个单位，得到点A2，则点A2的坐标是_________．14．如图，身高是1.6m的某同学直立于旗杆影子的顶端处，测得同一时刻该同学和旗杆的影子长分别为1.2m和9m.则旗杆的高度为________m.15．如图，在平面直角坐标系中，Rt△ABO的顶点O与原点重合，顶点B在x轴上，∠ABO=90°，OA与反比例函数y=kx的图象交于点D，且OD=2AD，过点D作x轴的垂线交x轴于点C．若S四边形ABCD=10，则k的值为．16．如果点A （－1，4）、B （m ，4）在抛物线y ＝a （x －1）2+h 上，那么m 的值为_____．17．如图，在矩形ABCD 中，过点A 的圆O 交边AB 于点E ，交边AD 于点F ，已知AD=5，AE=2，AF=1．如果以点D 为圆心，r 为半径的圆D 与圆O 有两个公共点，那么r 的取值范围是______．18．如图，点A （m ，2），B （5，n ）在函数k y x=（k ＞0，x ＞0）的图象上，将该函数图象向上平移2个单位长度得到一条新的曲线，点A 、B 的对应点分别为A′、B′．图中阴影部分的面积为8，则k 的值为．三、解答题：（本大题共9个小题，共78分，解答应写出文字说明、证明过程或演算步骤．19．（6分）如图，▱ABCD 中，点E ，F 分别是BC 和AD 边上的点，AE 垂直平分BF ，交BF 于点P ，连接EF ，PD ．求证：平行四边形ABEF 是菱形；若AB ＝4，AD ＝6，∠ABC ＝60°，求tan ∠ADP 的值．20．（6分）（1）计算：（12）﹣3×[12﹣（12）3]﹣4cos30°12；（2）解方程：x （x ﹣4）=2x ﹣821．（6分）校车安全是近几年社会关注的重大问题，安全隐患主要是超速和超载．某中学数学活动小组设计了如下检测公路上行驶的汽车速度的实验：先在公路旁边选取一点C ，再在笔直的车道l 上确定点D ，使CD 与l 垂直，测得CD 的长等于21米，在l 上点D 的同侧取点A 、B ，使∠CAD=30︒，∠CBD=60︒．(1)求AB 的长(精确到0.13 1.732 1.41≈≈，)；(2)已知本路段对校车限速为40千米／小时，若测得某辆校车从A 到B 用时2秒，这辆校车是否超速?说明理由．22．（8分）某商场计划购进A ，B 两种新型节能台灯共100盏，这两种台灯的进价、售价如下表：类型价格进价（元/盏）售价（元/盏）A 型30 45 B 型 50 70（1）若商场预计进货款为3500元，则这两种台灯各进多少盏．（2）若设商场购进A 型台灯m 盏，销售完这批台灯所获利润为P ，写出P 与m 之间的函数关系式．（3）若商场规定B 型灯的进货数量不超过A 型灯数量的4倍，那么A 型和B 型台灯各进多少盏售完之后获得利润最多？此时利润是多少元．23．（8分）如图，抛物线y=﹣12x 2﹣x+4与x 轴交于A ，B 两点（A 在B 的左侧），与y 轴交于点C ．（1）求点A ，点B 的坐标；（2）P 为第二象限抛物线上的一个动点，求△ACP 面积的最大值．24．（10分）已知，抛物线2:23L y x bx =--（b 为常数）．（1）抛物线的顶点坐标为( ， )（用含b 的代数式表示）；（2）若抛物线L 经过点()2,1M --且与k y x=图象交点的纵坐标为3，请在图1中画出抛物线L 的简图，并求k y x=的函数表达式；（3）如图2，规矩ABCD 的四条边分别平行于坐标轴，1AD =，若抛物线L 经过,A C 两点，且矩形ABCD 在其对称轴的左侧，则对角线AC 的最小值是．25．（10分）甲、乙两个人做游戏：在一个不透明的口袋中装有1张相同的纸牌，它们分别标有数字1，2，3，1．从中随机摸出一张纸牌然后放回，再随机摸出一张纸牌，若两次摸出的纸牌上数字之和是3的倍数，则甲胜；否则乙胜．这个游戏对双方公平吗？请列表格或画树状图说明理由．26．（12分）某销售商准备在南充采购一批丝绸，经调查，用10000元采购A 型丝绸的件数与用8000元采购B 型丝绸的件数相等，一件A 型丝绸进价比一件B 型丝绸进价多100元．（1）求一件A 型、B 型丝绸的进价分别为多少元？（2）若销售商购进A 型、B 型丝绸共50件，其中A 型的件数不大于B 型的件数，且不少于16件，设购进A 型丝绸m 件．①求m 的取值范围．②已知A 型的售价是800元/件，销售成本为2n 元/件；B 型的售价为600元/件，销售成本为n 元/件．如果50≤n≤150，求销售这批丝绸的最大利润w （元）与n （元）的函数关系式.27．（12分）如图，要在木里县某林场东西方向的两地之间修一条公路MN ，已知C 点周围200米范围内为原始森林保护区，在MN 上的点A 处测得C 在A 的北偏东45°方向上，从A 向东走600米到达B 处，测得C 在点B 的北偏西60°方向上．（1）MN 是否穿过原始森林保护区，为什么？（参考数据：3≈1.732）（2）若修路工程顺利进行，要使修路工程比原计划提前5天完成，需将原定的工作效率提高25%，则原计划完成这项工程需要多少天？参考答案一、选择题（本大题共12个小题，每小题4分，共48分．在每小题给出的四个选项中，只有一项是符合题目要求的．）1．C【解析】【分析】利用数轴先判断出a、b的正负情况以及它们绝对值的大小，然后再进行比较即可．【详解】解：由a、b在数轴上的位置可知：a＜1，b＞1，且|a|＞|b|，∴a+b＜1，ab＜1，a﹣b＜1，a÷b＜1．故选：C．2．D【解析】【分析】求得顶点坐标，得出顶点的横坐标和纵坐标的关系式，即可求得．【详解】抛物线y＝x2+（2a+1）x+a2﹣a的顶点的横坐标为：x＝﹣212a+＝﹣a﹣12，纵坐标为：y＝()()224214a a a--+＝﹣2a﹣14，∴抛物线的顶点横坐标和纵坐标的关系式为：y＝2x+34，∴抛物线的顶点经过一二三象限，不经过第四象限，故选：D．【点睛】本题考查了二次函数的性质，得到顶点的横纵坐标的关系式是解题的关键．3．C【解析】分析：根据众数的定义先求出x的值，再把数据按从小到大的顺序排列，找出最中间的数，即可得出答案．详解：∵数据1，2，x，5，6的众数为6，∴x=6，把这些数从小到大排列为：1，2，5，6，6，最中间的数是5，则这组数据的中位数为5；故选C.点睛：本题考查了中位数的知识点，将一组数据按照从小到大的顺序排列，如果数据的个数为奇数，则处于中间位置的数就是这组数据的中位数；如果这组数据的个数为偶数，则中间两个数据的平均数就是这组数据的中位数.4．B【解析】【分析】利用配方法求二次函数最值的方法解答即可．【详解】∵s=20t-5t2=-5（t-2）2+20，∴汽车刹车后到停下来前进了20m．故选B．【点睛】此题主要考查了利用配方法求最值的问题，根据已知得出顶点式是解题关键．5．A【解析】【分析】科学记数法的表示形式为a×10n的形式，其中1≤|a|<10，n为整数．确定n的值时，要看把原数变成a时，小数点移动了多少位，n的绝对值与小数点移动的位数相同．当原数绝对值>1时，n是正数；当原数的绝对值<1时，n是负数．【详解】2180000的小数点向左移动6位得到2.18，所以2180000用科学记数法表示为2.18×106，故选A.【点睛】本题考查科学记数法的表示方法．科学记数法的表示形式为a×10n的形式，其中1≤|a|<10，n为整数，表示时关键要正确确定a的值以及n的值．6．D【解析】【分析】设点B的横坐标为x，然后表示出BC、B′C的横坐标的距离，再根据位似变换的概念列式计算．【详解】设点B的横坐标为x，则B、C间的横坐标的长度为﹣1﹣x，B′、C间的横坐标的长度为a+1，∵△ABC放大到原来的2倍得到△A′B′C，∴2（﹣1﹣x）＝a+1，解得x＝﹣12（a+3），故选：D．【点睛】本题考查了位似变换，坐标与图形的性质，根据位似变换的定义，利用两点间的横坐标的距离等于对应边的比列出方程是解题的关键．7．B【解析】【分析】分别根据无理数、有理数的定义逐一判断即可得．【详解】解：在0，π，-3，0.6这5个实数中，无理数有π这2个，故选B．【点睛】此题主要考查了无理数的定义，注意带根号的要开不尽方才是无理数，无限不循环小数为无理数．如π，，0.8080080008…（每两个8之间依次多1个0）等形式．8．B【解析】【分析】<<.【详解】<∴34<，∴213<<﹣1的值在2和3之间.故选B.【点睛】的大小，在确定答案的范围.9．C【解析】在△ABC中，∠ACB=90°，∠A=24°，∴∠B=90°-∠A=66°．由折叠的性质可得：∠BCD=12∠ACB=45°，∴∠BDC=180°-∠BCD-∠B=69°. 故选C.10．C【解析】利用正方形的性质结合锐角三角函数关系得出正方形的边长，进而得出变化规律即可得出答案．解：如图所示：∵正方形A1B1C1D1的边长为1，∠B1C1O=60°，B1C1∥B2C2∥B3C3…∴D1E1=B2E2，D2E3=B3E4，∠D1C1E1=∠C2B2E2=∠C3B3E4=30°，∴D1E1=C1D1sin30°=，则B2C2===（）1，同理可得：B3C3==（）2，故正方形A n B n C n D n的边长是：（）n﹣1．则正方形A2017B2017C2017D2017的边长是：（）2．故选C．“点睛”此题主要考查了正方形的性质以及锐角三角函数关系，得出正方形的边长变化规律是解题关键．11．C【解析】【分析】科学记数法的表示形式为a×10n的形式,其中1≤a|<10,n为整数.确定n的值时,要看把原数变成a时,小数点移动了多少位,n的绝对值与小数点移动的位数相同.当原数绝对值>1时,n是正数;当原数的绝对值<1时,n 是负数.【详解】0.000 000 04=4×10-8,故选C【点睛】此题考查科学记数法，难度不大12．D【解析】先将25 100用科学记数法表示为2.51×104，再和10-9相乘，等于2.51×10-5米．故选D二、填空题：（本大题共6个小题，每小题4分，共24分．）13．（-1, -6）【解析】【分析】直接利用关于x轴对称点的性质得出点A1坐标，再利用平移的性质得出答案．【详解】∵点A的坐标是（-1，2），作点A关于x轴的对称点，得到点A1，∴A1（-1，-2），∵将点A1向下平移4个单位，得到点A2，∴点A2的坐标是：（-1，-6）．故答案为：（-1, -6）．【点睛】解决本题的关键是掌握好对称点的坐标规律：（1）关于x轴对称的点，横坐标相同，纵坐标互为相反数；（2）关于y轴对称的点，纵坐标相同，横坐标互为相反数；（3）关于原点对称的点，横坐标与纵坐标都互为相反数．14．1【解析】试题分析：利用相似三角形的相似比，列出方程，通过解方程求出旗杆的高度即可．解：∵同一时刻物高与影长成正比例．设旗杆的高是xm．∴1.6：1.2=x：9∴x=1．即旗杆的高是1米．故答案为1．考点：相似三角形的应用．15．﹣1【解析】【详解】∵OD=2AD，∴23 ODOA=，∵∠ABO=90°，DC⊥OB，∴AB∥DC，∴△DCO∽△ABO，∴23 DC OC ODAB OB OA===，∴22439 ODCOABSS⎛⎫==⎪⎝⎭VV，∵S四边形ABCD=10，∴S△ODC=8，∴OC×CD=8，OC×CD=1，∴k=﹣1，故答案为﹣1．16．1【解析】【分析】根据函数值相等两点关于对称轴对称，可得答案．【详解】由点A（﹣1，4）、B（m，4）在抛物线y=a（x﹣1）2+h上，得：（﹣1，4）与（m，4）关于对称轴x=1对称，m﹣1=1﹣（﹣1），解得：m=1．故答案为：1．【点睛】本题考查了二次函数图象上点的坐标特征，利用函数值相等两点关于对称轴对称得出m﹣1=1﹣（﹣1）是解题的关键．17r<<【解析】【分析】因为以点D为圆心，r为半径的圆D与圆O有两个公共点，则圆D与圆O相交，圆心距满足关系式：|R-r|<d<R+r，求得圆D与圆O的半径代入计算即可.【详解】连接OA、OD，过O点作ON⊥AE，OM⊥AF.AN=12AE=1，AM=12AF=2，MD=AD-AM=3∵四边形ABCD是矩形∴∠BAD=∠ANO=∠AMO=90°，∴四边形OMAN是矩形∴OM=AN=1∴=∵以点D为圆心，r为半径的圆D与圆O有两个公共点，则圆D与圆O相交r<<【点睛】本题考查了圆与圆相交的条件，熟记圆与圆相交时圆的半径与圆心距的关系是关键.18．2．【解析】试题分析：∵将该函数图象向上平移2个单位长度得到一条新的曲线，点A、B的对应点分别为A′、B′，图中阴影部分的面积为8，∴5﹣m=4，∴m=2，∴A（2，2），∴k=2×2=2．故答案为2．考点：2．反比例函数系数k的几何意义；2．平移的性质；3．综合题．三、解答题：（本大题共9个小题，共78分，解答应写出文字说明、证明过程或演算步骤．19．（1）详见解析；（2）tan∠ADP＝．【解析】【分析】（1）根据线段垂直平分线的性质和平行四边形的性质即可得到结论；（2）作PH⊥AD于H，根据四边形ABEF是菱形，∠ABC＝60°，AB＝4，得到AB＝AF＝4，∠ABF＝∠ADB＝30°，AP⊥BF，从而得到PH＝，DH＝5，然后利用锐角三角函数的定义求解即可．【详解】（1）证明：∵AE垂直平分BF，∴AB＝AF，∴∠BAE＝∠FAE，∵四边形ABCD是平行四边形，∴AD∥BC．∴∠FAE＝∠AEB，∴∠AEB＝∠BAE，∴AB＝BE，∴AF＝BE．∵AF∥BC，∴四边形ABEF是平行四边形．∵AB＝BE，∴四边形ABEF是菱形；（2）解：作PH ⊥AD 于H ，∵四边形ABEF 是菱形，∠ABC ＝60°，AB ＝4，∴AB ＝AF ＝4，∠ABF ＝∠AFB ＝30°，AP ⊥BF ，∴AP ＝AB ＝2，∴PH ＝，DH ＝5，∴tan ∠ADP ＝＝．【点睛】本题考查了菱形的判定及平行四边形的性质，解题的关键是牢记菱形的几个判定定理，难度不大． 20．（1）3；（1）x 1=4，x 1=1．【解析】【分析】（1）根据有理数的混合运算法则计算即可；（1）先移项，再提取公因式求解即可.【详解】解：（1）原式=8×（12﹣18）﹣4×323 =8×38﹣33=3；（1）移项得：x （x ﹣4）﹣1（x ﹣4）=0，（x ﹣4）（x ﹣1）=0，x ﹣4=0，x ﹣1=0，x 1=4，x 1=1．【点睛】本题考查了有理数的混合运算与解一元二次方程，解题的关键是熟练的掌握有理数的混合运算法则与根据因式分解法解一元二次方程.21．（1）24.2米(2) 超速，理由见解析【解析】【分析】（1）分别在Rt△ADC与Rt△BDC中，利用正切函数，即可求得AD与BD的长，从而求得AB的长．（2）由从A到B用时2秒，即可求得这辆校车的速度，比较与40千米/小时的大小，即可确定这辆校车是否超速．【详解】解：（1）由題意得，在Rt△ADC中，CDADtan30︒==，在Rt△BDC中，CDBDtan60===︒，∴AB=AD－BD=14 1.73=24.2224.2-≈⨯≈（米）．（2）∵汽车从A到B用时2秒，∴速度为24.2÷2=12.1（米/秒），∵12.1米/秒=43.56千米/小时，∴该车速度为43.56千米/小时．∵43.56千米/小时大于40千米/小时，∴此校车在AB路段超速．22．（1）应购进A型台灯75盏，B型台灯25盏；（2）P=﹣5m+2000；（3）商场购进A型台灯20盏，B 型台灯80盏，销售完这批台灯时获利最多，此时利润为1900元．【解析】【分析】（1）设商场应购进A型台灯x盏，表示出B型台灯为（100-x）盏，然后根据进货款=A型台灯的进货款+B型台灯的进货款列出方程求解即可；（2）根据题意列出方程即可；（3）设商场销售完这批台灯可获利y元，根据获利等于两种台灯的获利总和列式整理，再求出x的取值范围，然后根据一次函数的增减性求出获利的最大值．【详解】解：（1）设商场应购进A型台灯x盏，则B型台灯为（100﹣x）盏，根据题意得，30x+50（100﹣x）=3500，解得x=75，所以，100﹣75=25，答：应购进A型台灯75盏，B型台灯25盏；（2）设商场销售完这批台灯可获利P元，则P=（45﹣30）m+（70﹣50）（100﹣m），=15m+2000﹣20m，=﹣5m+2000，即P=﹣5m+2000，（3）∵B型台灯的进货数量不超过A型台灯数量的4倍，∴100﹣m≤4m，∴m≥20，∵k=﹣5＜0，P随m的增大而减小，∴m=20时，P取得最大值，为﹣5×20+2000=1900（元）答：商场购进A型台灯20盏，B型台灯80盏，销售完这批台灯时获利最多，此时利润为1900元．【点睛】本题考查了一次函数与一元一次方程的应用，解题的关键是熟练的掌握一次函数与一元一次方程的应用. 23．(1) A（﹣4，0），B（2，0）；(2)△ACP最大面积是4.【解析】【分析】（1）令y=0，得到关于x 的一元二次方程﹣12x2﹣x+4=0，解此方程即可求得结果；（2）先求出直线AC解析式，再作PD⊥AO交AC于D，设P（t，﹣12t2﹣t+4），可表示出D点坐标，于是线段PD可用含t的代数式表示，所以S△ACP=12PD×OA=12PD×4=2PD，可得S△ACP关于t 的函数关系式，继而可求出△ACP面积的最大值．【详解】(1)解：设y=0，则0=﹣12x2﹣x+4∴x1=﹣4，x2=2∴A（﹣4，0），B（2，0）(2)作PD⊥AO交AC于D设AC解析式y=kx+b∴404b k b=⎧⎨=-+⎩ 解得：14k b =⎧⎨=⎩∴AC 解析式为y=x+4.设P （t ，﹣12t 2﹣t+4）则D （t ，t+4） ∴PD=（﹣12t 2﹣t+4）﹣（t+4）=﹣12t 2﹣2t=﹣12（t+2）2+2 ∴S △ACP =12PD×4=﹣（t+2）2+4 ∴当t=﹣2时，△ACP 最大面积4.【点睛】本题考查二次函数综合，解题的关键是掌握待定系数法进行求解.24．（1）2,3b b --；（2）图象见解析，6y x =或9y x=-；（3 【解析】【分析】（1）将抛物线的解析式配成顶点式，即可得出顶点坐标；（2）根据抛物线经过点M ，用待定系数法求出抛物线的解析式，即可得出图象，然后将纵坐标3代入抛物线的解析式中，求出横坐标，然后将点再代入反比例函数的表达式中即可求出反比例函数的表示式；（3）设出A 的坐标，表示出C,D 的坐标，得到CD 的长度，根据题意找到CD 的最小值，因为AD 的长度不变，所以当CD 最小时，对角线AC 最小，则答案可求．【详解】解：（1）()2222222323()3y x bx x bx b b x b b =--=-+--=--+Q ， ∴抛物线的顶点的坐标为2(,3)b b --．故答案为：2(,3)b b --（2）将(2,1)M --代入抛物线的解析式得：4431b +-=- 解得：12b =-， ∴抛物线的解析式为23y x x =+-．抛物线L 的大致图象如图所示：将3y =代入23y x x =+-得： 233x x +-=，解得：2x =或3x =-∴抛物线与反比例函数图象的交点坐标为(2,3)或()3,3-．将(2,3)代入k y x=得：6k =， 6y x∴=．将()3,3-代入k y x=得：9k =-， 9y x=-∴．综上所述，反比例函数的表达式为6y x =或9y x=-．（3）设点A 的坐标为()2,23x x bx --，则点D 的坐标为()21,23x x bx +--， C 的坐标为21,(22)2)2(x x b x b ++---．()2223(22)22221DC x bx x b x b x b ⎡⎤∴=---+---=-+-⎣⎦ DC ∴的长随x 的增大而减小．Q 矩形ABCD 在其对称轴的左侧，抛物线的对称轴为x b =，1x b ∴+≤1x b ∴≤-∴当1x b =-时，DC 的长有最小值，DC 的最小值2(1)211b b =--+-=．AD Q 的长度不变，∴当DC 最小时，AC 有最小值．AC ∴的最小值222AD DC +=．【点睛】本题主要考查二次函数，反比例函数与几何综合，掌握二次函数，反比例函数的图象与性质是解题的关键．25．不公平【解析】【分析】列表得到所有情况，然后找出数字之和是3的倍数的情况，利用概率公式计算后进行判断即可得.【详解】根据题意列表如下：所有等可能的情况数有16种，其中两次摸出的纸牌上数字之和是3的倍数的情况有：（2，1），（1，2），（1，2），（3，3），（2，1），共5种，∴P （甲获胜）=516，P （乙获胜）=1﹣516=1116，则该游戏不公平．【点睛】本题考查了列表法或树状图法求概率，判断游戏的公平性，用到的知识点为：概率=所求情况数与总情况数之比．26．（1）一件A 型、B 型丝绸的进价分别为500元，400元；（2）①1625m ≤≤，②7512500(50100)5000(100)6611600(100150)n n w n n n -+≤<⎧⎪==⎨⎪-+<≤⎩．【解析】【分析】（1）根据题意应用分式方程即可；（2）①根据条件中可以列出关于m 的不等式组，求m 的取值范围；②本问中，首先根据题意，可以先列出销售利润y 与m 的函数关系，通过讨论所含字母n 的取值范围，得到w 与n 的函数关系．【详解】（1）设B 型丝绸的进价为x 元，则A 型丝绸的进价为()100x +元,根据题意得：100008000100x x=+，解得400x =，经检验，400x =为原方程的解，100500x ∴+=，答：一件A 型、B 型丝绸的进价分别为500元，400元．（2）①根据题意得：5016m m m -⎧⎨⎩„…， m ∴的取值范围为：1625m 剟，②设销售这批丝绸的利润为y ，根据题意得：()()()8005002600400?50y n m n m =--+---，()1001000050n m n =-+-50150n Q 剟，∴（Ⅰ）当50100n <„时，1000n ->，25m =时，销售这批丝绸的最大利润()2510010000507512500w n n n =-+-=-+；（Ⅱ）当100n =时，1000n -=，销售这批丝绸的最大利润5000w =；（Ⅲ）当100150n <„时，1000n -<当16m =时，销售这批丝绸的最大利润6611600w n =-+．综上所述：7512500(50100)50001006611600(100150)n n w n n n -+<⎧⎪==⎨⎪-+<⎩„„．【点睛】本题综合考察了分式方程、不等式组以及一次函数的相关知识．在第（2）问②中，进一步考查了，如何解决含有字母系数的一次函数最值问题．27．（1）MN 不会穿过森林保护区.理由见解析；（2）原计划完成这项工程需要25天.【解析】试题分析：（1）要求MN 是否穿过原始森林保护区，也就是求C 到MN 的距离．要构造直角三角形，再解直角三角形；（2）根据题意列方程求解．试题解析：（1）如图，过C 作CH ⊥AB 于H ，设CH=x，由已知有∠EAC=45°, ∠FBC=60°则∠CAH=45°, ∠CBA=30°，在RT△ACH中，AH=CH=x，在RT△HBC中，tan∠HBC=CH HB∴HB=tan30CHo=3=3x，∵AH+HB=AB∴x+3x=600解得x≈220（米）>200（米）．∴MN不会穿过森林保护区．（2）设原计划完成这项工程需要y天，则实际完成工程需要y-5根据题意得：15y=(1+25％)×1y，解得：y=25知：y=25的根．答：原计划完成这项工程需要25天．。

河南重点高中2019-2020学年度高一上学期物理第五周周测试卷及答案

绝密★启用前河南重点高中2019-2020学年度高一上学期周测（5）物理试卷考试时间：60分钟；命题人：高科；审题人：高一物理组一、单选题1．下列有关质点或参考系的说法中正确的是A．研究自行车的运动时，在任何情况下都不能把自行车视为质点B．虽然地球很大，还在不停地自转，但是在研究地球的公转时，仍然可以把它视为质点C．参考系是在描述物体运动时，用来做参考的物体，必须选静止的物体D．参考系可以任意选择，并且选择不同的物体做参考系来描述同一个物体的运动时，结果是相同的2．下列物理量中，属于矢量的是A．路程B．时间C．速率D．加速度3．横跨杭州湾的嘉绍大桥是世界上最长、最宽的多塔斜拉桥，全长10.137千米，设计速度为100千米/小时。

某辆汽车通过嘉绍大桥的记录显示：17：33分进入嘉绍大桥，17：43分离开大桥。

下列说法正确的是A．该汽车经过嘉绍大桥的位移是10.137kmB．“设计速度为100千米/小时”该速度为平均速度C．研究该汽车通过嘉绍大桥的时间时，可以将该汽车视为质点D．该汽车通过嘉绍大桥的平均速度约为60.8km/h4．打点计时器是记录做直线运动的物体位置和时间的仪器，利用打点计时器打出的纸带，可以获得运动物体的相关信息．下列信息不能获得的是A．物体运动的时间B．物体在不同时刻的位置C．物体的质量D．物体速度变化的情况5．M99是我国一款性能先进的大口径半自动狙击步枪。

步枪枪管中的子弹从初速度为零开始，经0.0016s的时间离开枪管被射出，已知子弹在枪管内的平均速度是500m/s，射出枪口的速度是800m/s，则枪管的长度是A．0.80m B．1.28m C．0.64m D．1.04m6．一物体做匀变速直线运动，加速度为2m/s2，则下列说法正确的是A．物体一定做加速运动B．每秒的末速度都比初速度大2m/s C．第2秒末的速度是第1秒末速度的2倍D．每秒速度的变化量为2m/s 7．何雯娜拿下了北京奥运蹦床项目的冠军头衔，获得了中国蹦床史上首枚金牌。

2019-2020年七年级英语下册第5周周测试卷

2019-2020学年下学期七年级周测卷英语（学科）试卷时间：50分钟分值：100分阅读下面五篇语言材料，然后按要求做题。

（25小题，每小题4分）(A)Y ou frown (皱眉). Y ou raise your eyebrows. Y ou roll your eyes. What are you doing? Y ou are making facial expressions.Facial expressions are one or more movements on a person’s face. Scientists say that humans have 80 muscles (肌肉) in their faces. These muscles can make 7,000 different facial expressions.These expressions can be put into six categories (类别). They are happiness, sadness, anger, surprise, fear and disgust (厌恶). For example, when people think a certain food tastes disgusting, they usually make a funny face. When people are surprised, they often raise their eyebrows and open their eyes wide.Facial expressions are important for communicating (交流). If people can read facial expressions correctly, they may be better at knowing other people’s feelings. That can help people make more friends.However, sometimes people have to be careful when reading others’faces. For example, it is not a good idea to stare at (盯着看) others for a long time. They may think you are rude.1. How many facial expressions can we see on a face?A. 80B. 7,000C. 6D. 4802. What will the face look like when somebody tastes disgusting food?A. The eyebrows are frowning.B. The face looks funny.C. Their eyes are rolling quickly.D. Their eyes are widely open.3. What is the main idea of the fourth paragraph?A. Reading facial expressions can be helpful in daily life.B. We need learn how to make friends in life.C. It is not always good to read others’ facial expressions.D. People can’t always read others’ facial expressions correctly.4. What does the word “rude” in the last paragraph mean?A. 友善的B. 傻乎乎的C. 健谈的D. 粗鲁的(B)A siheyuan is a kind of traditional home for Chinese people. Siheyuan in Beijing are the most common ones.A siheyuan has a big square (正方形的) courtyard (院子) in the center. There are four buildings around the yard. Usually, one siheyuan is for one family to live in.Siheyuan follow Confucian (儒家的) ideas of respecting authority (权威) and the elderly. The northern main house receives the most sunshine. The eldest member of the family lives there. The east and west houses are for the second and third generations (一代人). The southern building is closest to the gate. It is usually for servants (仆人) or guests.Living in a siheyuan helps to keep every family member close. As time went on, siheyuan also became like big neighborhoods for many different families. They shared happy and sad times in the same yard.Today, tall buildings have replaced (代替) many siheyuan. In order to protect(保护) them, the government did a census (普查). Nearly 1,000 of these buildings will be featured in The Records of Beijing Siheyuan (《北京四合院志》).5. Which of the following facts about siheyuan is correct?A. A siheyuan is a square yard.B. Many families would live together in a siheyuan in the past.C. There are more than four buildings in the yard.D. People now usually live in buildings like siheyuan.6. The oldest family members usually lived in _____.A. the northern houseB. the western houseC. the southern houseD. the eastern house7. Paragraph 4 talks about _____.A. where people live in a siheyuanB. the nice things about living in a siheyuanC. how big a siheyuan isD. the jobs people did in siheyuan8. To protect siheyuan, the government _____.A. bought many siheyuan from peopleB. did a census and featured them in a bookC. replaced siheyuan with many tall buildingsD. built 1,000 siheyuan in Beijing(C)There are some similarities (相似之处) and some differences between growing up inAustralia and China.I grew up in a small town of about 20,000 people called Gympie on the east coast (海岸) of Queensland. Each weekday morning, I woke up at about 7 am and got ready for school. My favorite cereal (谷物) was called Weet-Bix.As well as playing sports, I also played the saxophone (萨克斯管). Some mornings,I went to school early for band practice before going to class. English and PE were my favorite subjects in school. My friends and I played tag (捉人游戏) or handball during our lunch breaks. School finished at 3 pm. After that, I would usually go to sports practice. In summer I played cricket (板球) and in winter I played hockey (冰球). Sometimes I played tennis too!When I finally got home, I was very tired. My mother or father cooked dinner. Then I did my homework and read a book. I always went to sleep before 9 pm.On the weekend I played sports, visited a friend’s house or watched TV.Gympie was a great place to grow up!9. What do we know about the writer’s hometown?A. There are much more than 20,000 people living there.B. It is on the west coast of Australia.C. The name of the town is Gympie.D. Life there is quite like life in China.10. The writer sleeps for about _____ on weekdays.A. 6 hoursB. 8 hoursC. 10 hoursD. 12 hours11. On weekends, the writer might _____.A. watch TV at homeB. cook dinner with his parentsC. play tag during lunchD. practice the saxophone12. What does the writer think about his hometown?A. He enjoys life in his hometown.B. There are many people who are good at sports.C. He thinks his hometown is as good as China.D. His hometown is a good place to read books.(D) T ech lends a handIn the fight against the new virus, China has used lots of powerful technologies (技术). They help scientists find treatments (疗法) for the virus, as well as control the infection (传染).In recent years, new technologies, such as supercomputers (超级计算机) and drones (无人机), have made progress in China. Now they are playing a big role in fighting the new virus.vSupercomputers can run faster than ordinary ones. Supercomputers can also analyze (分析) the genetic data (基因数据) of the virus and help scientists learn more about the virus in order to make vaccines (疫苗). Chinese companies like Tencent have opened up their supercomputers to scientists, helping them analyze medicine and find treatments for the virus. Drones and robots are also giving a hand. They not only make work easier for people, but also prevent cross-infection (交叉感染). Chinese company DJI makes drones that can spray disinfectant (喷洒消毒剂) and give information. If people gather in large groups or do not wear masks, drones can warn them. The DJI drones have gone to more than 50 cities in 18 provinces.Robots can do work at hospitals, as well as help delivery (快递) workers. For example, e-commerce company JD is using robots to send packages (包裹) in Wuhan. Other robots bring medicine or meals to patients, conduct (进行) disinfection or check patients’body temperatures. Outside of hospitals, robots help check people’s temperatures in public places like train stations and airports (机场).13. From Paragraph 1, we know that _____.A. new technologies are being used to fight the virusB. all technologies are useful in fighting diseasesC. China tries to make more new technologiesD. China has the best technology in the world14. Why did Tencent open up their supercomputers?A. Because the company wants to sell more medicine.B. Because the company wants to collect information about the virus.C. Because the company wants to help scientists find treatments.D. Because the company can make vaccines this way.15. What does “giving a hand” mean in Paragraph 3?A. To make something new.B. To help someone out.C. To do something useless.D. To buy expensive things.16. What can robots do to fight the virus, according to the story?a. Work as doctors in hospital.b. Bring food to patients.c. Check body temperatures.d. Conduct disinfection.A. abcB. bcdC. acdD. abd(E) Going to school onlineFeb 17 should have been the start of the spring semester for many middle and primary schools in China. However, to control the new coronavirus outbreak (新型冠状病毒疫情), many schools have delayed (延迟) the start of the semester, following instructions from the Ministry of Education (MOE).uBut students in China are still studying.Instead of having class at school, many students in Beijing and Guangzhou began their first day of online classes on Feb 17. Students in Shanghai will start online classes on March 2.“In the morning, I have English class, followed by Chinese and math,” Liu Bo, a Junior 3 stud ent from Beijing, told Xinhua. “I have also learned about epidemic prevention.”According to the MOE, students are mainly taking classes to review previous knowledge rather than taking new classes during the online study period. Online courses are required to include content about epidemic prevention, psychological health (心理健康) and educational activities (教育活动).“Online courses are only temporary measures (暂时的措施) taken during the epidemic, sowhen the new semester begins, schools should not replace (替代) classroom teaching with online classes,” Lü Y ugang from the ministry told China Daily.The ministry also called on schools not to increase their students’ schoolwork burden (负担). Schools should not ask students to study online for long periods of time or study things beyond (超出) their curriculum (课程). Students must have enough time to rest, the ministry added. Also, it stressed that protecting students’ eyesight must be a priority (优先).17. Many Beijing students are taking online courses these days because _____.A. it’s more convenient to have class onlineB. Spring Festival is not finished yetC. they need more time to rest at homeD. it can help control the NCP outbreak18. The online courses focus more on _____.a. reviewing previous knowledgeb. taking new classesc. learning about infection preventiond. learning about psychological healthA. abcB. abdC. acdD. bcd19. What can we learn from Lü Yugang?A. Online courses can’t replace classroom teaching.B. Online courses will last for a long time.C. Online courses should not be used in the future.D. Online courses should be widely developed.20. The story talks about many aspects of online courses except _____.A. when the online courses startB. what the online courses teachC. how to properly provide online coursesD. how students take exams through online courses(F)Everyone has different opinions. It is easy to express your own opinions. But you should becareful about how you express your opinions.21_____________Firstly, listen carefully to others. Although you may be eager to explain your side , listening to someone else explain your side, listening to someone else explain their first will help keep the conversation calm.22____________________Secondly, think twice before you act.23.______________________________Don’t talk back directly, which isn’t quite proper, since you may say out something that is incorrect without thinking.24.__________________________Remember, you’re not trying to start an argument. Don’t try to force your friends to think like you. More importantly, don’t use some dirty words to talk about others’ opinions.Lastly, show your friends that you value your friendship.25._________________________Real friends respect each other.A.Next, express your opinions politely.B.Y ou will also better understand their side.C.Here is some advice about how to express your opinions.D.When others disagree with you, you should think more about it.E.Y ou never worry about talking to your friends about what you really think.。

2019-2020学年上海市上海外国语大学附属中学九年级(上)第二周周测卷(删除听力)(Word版无

2019-2020学年度上海市上海外国语大学附属中学九年级（上）第2周周测卷II. Multiple choiceA. Grammar11. Traveling during National Day is not a wise choice as all the places are crowded, while dining out in restaurants during Spring Festival can save a lot of trouble in preparing dinner.A. the, theB. the, /C. /, theD. /, /12. I’d like to buy these pencils.A. three dozenB. dozen ofC. three dozens ofD. a dozen13. The new area of the city is about the old one.A. three times the size asB. three times the size ofC. three times that isD. three times what is14. With so much work to do, you to the concert last night.A. mustn’t goB. shouldn’t goC. mustn’t have goneD. shouldn’t have gone15. Starting around 7000 B.C., and for the next four thousand years, much of the Northern Hemispheretemperature warmer than at present.A. experiencesB. will experienceC. experiencedD. had experienced16. , but he still couldn’t understand the logical connection of the two subjects.A. Having told many timesB. Having been told many timesC. He was told many timesD. Many times as he was told17. The conference currently in Geneva has caught the attention of the mass media.A. heldB. to be heldC. being heldD. having held18. --Well, where did you spend your night that day?--At .A. where it is called Hilton HotelB. what is called Hilton HotelC. which is called Hilton HotelD. that is called Hilton Hotel19. The newly built café, are painted light green, is really a peaceful place for us, specially after hard work.A. the walls of whichB. the walls of itC. its wallsD. of which walls20. Because of the financial crisis, days are gone local 5-star hotels charged 6,000 yuan for one night.A. ifB. whenC. whichD. since21. that witnessed the emergence of and the ongoing debate over genetically modified food.A. During the first 10 years in the 21st centuryB. That it was in the first 10 years of the 21st centuryC. It was in the first 10 years of the 21st centuryD. It was the first 10 years of the 21st century22. different life today is from it was fifty years ago!A. What a, whatB. What a, howC. How, whatD. What, what23. your free time to create and grow, and you will find yourself living a more meaningful life.A. UsingB. UseC. To useD. If use24. --You said she wouldn’t come, ?--Yes, but she changed her mind.A. didn’t youB. did youC. would sheD. wouldn’t she25. Not only shade and beauty, but carbon dioxide in the atmosphere.A. do threes provides, they also absorbB. tree provide, they also absorbC. provide trees, also absorb theyD. do trees provide, also do they absorb26. , it was regarded as a matter of no account in his time.A. Important although his discovery isB. Important as his discovery isC. As his discovery is important B. No matter important his discovery is27. for the economic downturn, the unemployment wouldn’t be shrinking so rapidly.A. Had it not beenB. Were it notC. Hadn’t it beenD. Were not it28. His pale face suggested that he able to continue with the test, so we all suggested that hea rest to recover his strength.A. was not, hasB. shouldn’t not be, haveC. was not, haveD. should not be, has29. --You couldn’t have chosen any gift better for me.-- .A. Oh, I’d choose a better one for you next time.B. You’ve had a gift for music, haven’t you?C. I’m glad that you like it so much.D. Sorry but don’t blame me, dear.30. Believe it or not, can you all expect to be admitted to some famous universities.A. with high marksB. whatever high marksC. by working hardD. only with high marksB. Vocabulary31. He from his family and settled down in America.A. broke awayB. broke outC. broke upD. broke in32. He had to his father’s business after his death, though he didn’t really want to continue it.A. carry outB. pick upC. set upD. carry on33.Fortunately,with the help of some local villagers,rescuers were able to gainto the disaster-hit area soon enough.A. trackB. accessC. meansD. passage34.The municipal government has launched aagainst smoking in public places such as restaurants and theatres.A. warB. battleC. fightD. campaign35. My children are not about the food—they eat whatever I cook.A. particularB. specialC. especialD. peculiar36. Watch out! Don’t step on the ice or it’s easy to .A. crashB. crackC. crushD. smash37. When I took his temperature, it was two degrees above .A. averageB. ordinaryC. regularD. normal38. These plastic flowers look so that many people think they are real.A. beautifulB. naturalC. artificialD. similar39. The open university was started in order to help those who having a university education when they were young.A. stoppedB. failedC. missedD. ceased40. It’s bad for a man to smoke in the public places where smoking is not allowed.A. behaviorB. actionC. mannerD. movementIII. ClozeThe requirements for high school graduation have just changed in my community. As a result, all students must 41 sixty hours of service learning or they will not receive a diploma. Service learning is academic learning that also helps the community. 42 of service learning include cleaning up a polluted river, working in a soup kitchen, or tutoring a student. 43 a service experience, students mustkeep a journal and then write a report about what they have learned.Supporters claim that there are many benefits of service learning. Perhaps most importantly, students are forced to think 44 their own interests and become aware of the needs of others. Students are also able to learn real life skills that 45 responsibility, problem-solving, and working as part of a team. Finally, students can explore possible careers through service learning.For example, if a student wonders what teaching is like, he or she can choose to work in an elementary school classroom a few afternoons each month. 46 there are many benefits, opponents point out problems with the new requirement. First, they 47 that the main reason students go to school is to learn core subjects and skills. Because service learning is time consuming, students spend48 time studying the core subjects. Second, they believe that forcing students to work without pay goes against the law. By requiring service, the school takes away an individual’s freedom to choose.In my view, service learning is a great way to contribute to the community, learn new skills, and explore different careers. 49 , I don’t believe you should force people to help others--the desire to help must come from the heart. I think the best 50 is one that gives students choices: a student should be able to choose sixty hours of independent study or sixty hours of service. Choice encourages both freedom and responsibility, and as young adults, we must learn to handle both wisely.41. A. spend B. gain C. complete D. save42. A. Subjects B. Ideas C. Procedures D. Examples43. A. With B. Before C. During D. After44. A. beyond B. aboutC. over D. in45. A. possess B. applyC. include D. develop46. A. So B. Thus C. SinceD. While47. A. argue B. doubt C. overlook D. admit48. A. much B. full C. less D. more49. A. Therefore B. Otherwise C. Besides D. However50. A. decision B. purpose C. solution D. resultIV. Reading comprehension(A)Generations of children grew up reading comic books secretly, hiding out from parents and teachers who saw them as a waste of time and a risk to young minds. Comics are now gaining a new respectability at school. That is thanks to an increasingly popular and creative program, often aimed at struggling readers, that encourages children to plot, write and draw comic books, in many cases using themes from their own lives.The Comic Book Project was started in 2001 by Michael Bitz at an elementary school in Queens. Since its creation, the program, which is mainly conducted after school, has spread to more than 850 schools across the country. It has gotten a big push from the Canent craze among adolescents for comic book clubs and for Manga, a wildly popular variety of comic originating in Japan.The point is not to drop a comic book on a child’s desk and say: “read this”. Rather, the workshops give groups of students the opportunity to collaborate on often complex stories and characters that they then revise, publish and share with others in their communities.Teachers are finding it easier to teach writing, grammar and punctuation with material that students are fully invested in. And it turns out that comic books have other built-in advantages. The pairing of visual and written plotlines that they rely on appear to be especially helpful to struggling readers. No one is suggesting that comic books should substitute for traditional books or for standard reading and composition lessons. Teachers who would once have dismissed comics out of hand are learning to exploita style that clearly has a powerful hold on young minds. They are using what works.51. Which of the following is probably the best title of the passage?A. Japanese Comic Books.B. Comic Books in the Classroom.C. Reading Efficiently.D. A Current Craze.52. Which of the following is TRUE according to the passage?A. Students’reading materials are often involved with their daily life.B. Comic books can now take the place of textbooks at school.C. Teachers now give away comic books for children to read.D. Children’s imagination plays a key role in comic books.53. The underlined phrase “its” in Paragraph 2 probably refers to .A. the Comic Book Project’sB. an elementary school’sC. Queens’D. the country’s54. The main purpose of the Comic Book Project is to .A. develop the cooperation among adolescentsB. make sure that students live a rich and colorful life after schoolC. help students who have some difficulty in readingD. popularize a new method of teaching55. It can be inferred that .A. comic books were first used in Japanese schoolsB. parents have different opinions about their children reading comic booksC. more and more teachers will realize the advantages of comic booksD. comic books will be allowed to enter all the schools in the country(B)On her first morning in America last summer, my daughter went out to explore her new neighborhood alone, without even telling my wife or me.Of course we were worried; we had just moved from Berlin, and she was just 8. But when she came home, we realized we had no reason to panic. Beaming with pride, she told us how she had discovered the little park around the corner, and had made friends with a few local dog owners. She had taken possession of her new environment, and was keen to teach us things we didn’t know.When this story comes up in conversations with American friends, we are usually met with polite disbelief. Most are horrified by the idea that their children might roam around without adult supervision. In Berlin, where we lived in the center of town, our girls would ride the Metro on their own – a no-no in Washington. Or they’d go alone to the playground or walk a mile to a piano lesson. Here in quiet and traffic-safe suburban Washington, they don’t even find other kids on the street to play with. On Halloween, when everybody was out to trick or treat, we were surprised by how many children actually lived here whom we had never seen.A study by the University of California has found that American kids spend 90 per cent of their leisure time at home, often in front of the TV or playing video games. Even when kids are physically active, they are watched closely by adults, either in school, at home, at afternoon activities or in the car, shuttling them from place to place.Such narrowing of children’s world has happened across the developed world. But German parents are generally much more accepting of letting children take some risks. To them, it seems that American’s middle class has taken overprotective parenting to a new level, with the government acting as a super nanny.But when it comes to their own children, the same respondents were terrified by the idea of givingthem only a little of the freedom they once enjoyed. Many cited fear of abduction, even though crime rates have declined significantly. The most recent in-depth study found that, in 1999, only 115 children nationwide were victims of a “stereotypical kidnapping”by a stranger; the majority was abducted by a family member. The same year, 2931 children under 15 died as passengers in car accidents. Driving children around is statistically more dangerous than letting them roam freely.“We are depriving them of opportunities to learn how to take control of their own lives,” writes Peter Gray, a research professor at Boston College. He argues that this increases the chance that they will suffer from anxiety, depression, and various other mental disorders, which have gone up dramatically in recent decades.I am no psychologist like Professor Gray, but I know I won’t be around forever to protect my girls from the challenges life holds in store for them. And by giving kids more control over their lives, they learn to have more confidence in their own capabilities.56. Hearing the author’s daughter exploring the new neighborhood alone, his American friends feel .A. worriedB. proudC. doubtfulD. terrified57. We can conclude from Paragraph 3 that .A. American kids enjoy playing at homeB. German parents are less protective than American parentsC. German kids like taking risks more than American kidsD. American parents don’t limit their children’s activities in their leisure time58. In which of the following countries isn’t narrowing of the child’s world likely to happen?A. AmericaB. IndiaC. JapanD. England59. It’s implied from Professor Gray’s words that .A. parents should always be around their children to protect them from risksB. more and more parents suffer from mental problemsC. children are having more opportunities to take control of their livesD. giving children more freedom is beneficial to their mental development60. Which of the following words can best describe the author’s parenting?A. Open-mined.B. Irresponsible.C. Careless.D. Protective.(C)Glaciers are large masses of ice on land that show evidence of past or present movement. They grow by the gradual transformation of snow into glacier ice.A fresh snowfall is a fluffy mass of loosely packed snowflakes, small delicate ice crystals grown in the atmosphere. As the snow ages on the ground for weeks or months, the crystals shrink and become more compact, and the whole mass becomes squeezed together into a more dense form, granular snow. As new snow falls and buries the older snow, the layers of granular snow further compact to form firm, a much denser kind of snow, usually a year or more old, which has little pore space. Further burial and slow cementation – a process by which crystals become held together in a mosaic of intergrown ice crystals –finally produce solid glacial ice. In this process of recrystallization, the growth of new crystals at the expense of old ones, the percentage of air is reduced from about 90 percent for snowflakes to less than 20 percent for glacier ice. The whole process may take as little as a few years, but more likely ten or twenty years or longer. The snow is usually many meters deep by the time the lower layers are converted into ice.In cold glaciers those formed in the coldest regions of the Earth, the entire mass of ice is at temperatures below the melting point and no free water exists. In temperate glaciers, the ice is at the melting point at every pressure level within the glacier, and free water is present as small drops or aslarger accumulations in tunnels within or beneath the ice.Formation of a glacier is complete when ice has accumulated to a thickness (and thus weight) sufficient to make it move slowly under pressure, in much the same way that solid rock deep within the Earth can change shape without breaking. Once that point is reached, the ice flows downhill, either as a tongue of ice filling a valley or as thick ice cap that flows out in directions from the highest central area where the most snow accumulates. The trip down leads to the eventual melting of ice.61. Which of the following does the passage mainly discuss?A. The effect of glaciers on climate.B. Damage from glaciers.C.Glacier formation. D. The location of glaciers.62. Which of the following will cause density within the glacier to increase?A. Increased water and air content.B. Pressure from the weight of new snow.C. Long periods of darkness and temperature variations.D. Movement of the glacier.63. Which of the following will be lost if a glacier forms?A. AirB. PressureC. WeightD. Rocks64. What is the purpose of the material in paragraph 3?A. To define two types of glaciers.B. To contrast glacier ice with non-glacier ice.C. To present theories of glacier formation.D. To discuss the similarities between glacial types.65. It can be inferred from the last paragraph that a glacier .A. can revert to a fluffy massB. maintains the same shape throughout the glacial processC. is too cold to be thoroughly studiedD. can contribute water to lakes, rivers, or oceansPart TwoI. Fill in the blanks with proper words. The first letter is given.As more and more people speak the global languages of English, Chinese, Spanish, and Arabic, other languages are rapidly d 1 . In fact, half of the 6,000-7,000 languages spoken around the world today will likely die out by the next century, according to the United Nations Educational, Scientific, and Cultural Organization (UNESCO).In an e 2 to prevent language loss, scholars from a number of organizations- UNESCO and National Geographic among them –have for many years been documenting dying languages and the c 3 they reflect.Mark Turin, a scientist at the Macmillan Center, Yale University, who specializes in the languages and oral traditions of the Himalayas, is following in that tradition. His recently published book, A Grammar of Thangmi with an Ethnolinguistic Introduction to the Speakers and Their Culture, grows out of his e 4 living, looking and raising a family in a village in Nepal.Documenting the Tangmi language and culture is just a starting p 5 for Turin, who seeks to i 6 other languages and oral traditions across the Himalayans reaches of India, Nepal, Bhutan, and China. But he is not content to simply record these v 7 before they disappear without record.At the University of Cambridge Turin discovered a wealth of important m8- including photographs, films, tape recordings, and field notes- which had remained unstudied and were badly in need of care and p 9 .Now, through the two organizations that he has founded-the Digital Himalaya Project and the World Oral Literature Project- Turin has started a campaign to make such documents, found in libraries and stores around the world, a 10 not just to scholars but to the youngers.II. Word transformation. Each word can be used only once.Every day we experience one of the wonders of the world around us without even realizing it. It is not the amazing complexity of television, nor the 1 technology of transport. The 2 wonder we share and experience is our ability to make noise without mouths, and so transmit ideas and thoughts to each other’s minds. This ability comes so 3 that we tend to forget what a miracle it is.Obviously, the ability to talk is something that marks humans off from animal. Of course, some animals have powers just as amazing. Birds can fly thousands miles by 4 positions of the stars in the sky in 5 to the time of day and year. In Nature’s talent show, humans are a species of animal that have developed their own special act. If we reduce it to basic terms, it’s an ability for communicating information to others, by varying sounds we make as we breathe out.Not that we don’t have other powers of communication. Our facial 6 convey our emotions, such as anger, or joy, or 7 . The way we hold our heads can indicate to others whether we are happy or sad. This is so-called “bod y language”. Bristling (直立的) fur is an unmistakable warning of attack among many animals. 8 , the bowed head or drooping tail shows a readiness to take second place in any animal gathering.Such a means of communication is a basic mechanism that animals, including human beings, instinctively( 本能地) acquire and display. Is the ability to speak just another sort of instinct? If so, how did human beings acquire this amazing skills? 9 can readily indicate that particular area of our brain where speech mechanisms function, but this doesn’t tell us how that part of our bodies 10 in our biological history.III. Fill in the blanks with the proper form of each verb given.Four people in England back in 1953, stared at Photo 51. It wasn’t much—a picture 1 (show) a black X. But three of these people won the Nobel Prize for figuring out what the photo really showed—the shape of DNA. The discovery brought fame and fortune to scientists James Watson, Francis Crick, and Maurice Wilkins. The fourth, the one who actually made the picture, 2 (leave out).Her name was Rosalind Franklin. “She should have been up there,” says historian Mary Bowden. “If her photo 3 (not be) there, the others 4 (can’t come up) with the structure.” O ne reason Franklin was missing was that she 5 (die) of cancer four years before the Nobel decision. But now scholar doubt that Franklin was not only robbed of her life by disease but robbed of credit by her competitions.At Cambridge University in the 1950s, Watson and Crick tried to make models by cutting up shapes of DNA’s parts and then putting them together. In the meantime, at King’s College in London, Franklin andWilkins shone X-rays at the molecule (分子). The rays produced patterns reflecting the shape.But Wilkins and Franklin’s relationship was a lot rockier than the celebrated teamwork of Watson and Crick. Wilkins thought Franklin was hired to be his assistant. But the college actually employed her 6 (take over) the DNA project.What she did was produce X-ray pictures that told Watson and Crick that one of their early models was inside out. And she was not shy about saying so. That angered Watson, who attacked her in return,“M ere inspection suggested that she 7 (not bend) easily. Clearly she had to go or be put in her place.”As Franklin’s competitors, Wilkins, Watson and Crick had much to gain by cutting her out of the little group of researchers, says historian Pnina Abir-Am. In 1962 at the Nobel Prize awarding ceremony, Wilkins thanked 13 colleagues by name before he mentioned Franklin. Watson wrote his book laughing at her. Crick wrote in 1974 that “Franklins was only two steps away from the solution.”No, Franklin was the solution. “She contributed more than any other player to 8 (solve) the structure of DNA. She must 9 (consider) a co-discoverer,” Abir-Am says. This was backed up by Aaron Klug, who worked with Franklin and later won a Nobel Prize himself. Once 10 (describe) as the “Dark Lady of DNA”, Franklin is finally coming into the light.IV. Sentence transformation.1. My grandpa had an operation two years ago, so he is able to live in good health now. (改写成虚拟倒装句)2. The little girl didn’t fall asleep until her mother told her a bed-time story. (就划线部分改写成强调句)3. As soon as Bruce shook hands with us, the phone rang.Scarcely .4. As the bus driver had braked in time, he avoided bumping into the boy who was running. (用分词结构改成简单句)5. The chemical plant near our home discharges lots of toxic materials into the river. We worry about it. (改成一句含有主语从句与表语从句的复合句)V. Read the following passage and answer the questions.As researchers learn more about how children’s intelligence develops, they are increasingly surprised by the power of parents. The power of the school has been replaced by the home. To begin with, all the factors which are part of intelligence—the child’s understanding of language, learning patterns, curiosity —are established well before the child enters school at the age of six. Study after study has shown that even after school begins, children’s achievements have been far more influenced by parents than by teachers. This is particularly true about learning that is language-related. The school rather than the home is given credit for variations in achievement in subjects such as science.In view of their power, it’s sad to see so many parents not making the most of their child’s intelligence. Until recently parents had been warned by educators who asked them not to educate their children. Many teachers now realize that children cannot be educated only at school and parents are being asked to contribute both before and after the child enters school.Parents have been particularly afraid to teach reading at home. Of course, children shouldn’t be pushed to read by their parents, but educators have discovered that reading is best taught individually—and the easiest place to do this is at home. Many four- and five-year-olds who have been shown a few letters and taught their sounds will compose single words of their own with them even before they have been taught to read.1. What have researchers found out about the influence of parents and the school on children’s intelligence?2. What do researchers conclude about children’s learning patterns?3. In which area may school play a more important role?4. Why did many parents fail to make the most of their children’s intelligence?5. The author suggests in the last paragraph that parents should be encouraged .VI. Translation.1. Jack 是一个如此健谈的人以至于我得提醒他别扯太远了。

河北省黄骅市黄骅中学2019-2020学年高一下学期英语周测练习题 Word版含答案

黄骅中学2019－2020年度第二学期高中一年级网上周考四英语试卷诚信考试从我做起The measure of a man’s real character is what he would do if he knew he wouldnever be found out.—Thomas Macaulay 本试卷分第Ⅰ卷（阅读理解）和第Ⅱ卷( 英语知识运用）两部分。

第Ⅰ卷1至5 页，第Ⅱ卷5 至8 页。

共90分。

考试时间60分钟。

第Ⅰ卷（阅读理解共30 分）第一部分阅读理解（共两节，满分30分）第一节（共8小题，每小题2.5分，满分20分）阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。

AYour house may have an effect on your figure . Experts say the way you design your home could play a role in whether you pack on the pounds or keep them off. You can make your environment work for you instead of against you. Here are some ways to turn your home into part of your diet plan.Open the curtains and turn up the lights. Dark environments are more likely to encourage overeating, for people are often less self-conscious(难为情) when they’re in poorly lit places –and so more likely to eat lots of food. If your home doesn’t have enough window light, get more lamps and flood the place with brightness.Mind the colors. Research suggests warm colors fuel our appetites. In one study, people who ate meals in a blue room consumed 33 percent less than those in a yellow or red room. Warm colors like yellow make food appear more appetizing, while cold colors make us less hungry. So when it’s time to repaint, go blue.Don’t forget the c lock – or the radio. People who eat slowly tend to consume about 70 fewer calories(卡路里)per meal than those who rush through their meals. Begin keeping track of the time, and try to make dinner last at least 30 minutes. And while you’re at it, actually sit down to eat. If you need some help slowing down, turn on relaxing music. It makes you less likely to rush through a meal.Downsize the dishes. Big serving bowls and plates can easily make us fat. We eat about 22percent more when using a 12-inch plate instead of a 10-inch plate. When we choose a large spoonover a smaller one, total intake(摄入) jumps by 14 percent. And we’ll pour about 30 percentmore liquid into a short, wide glass than a tall, skinny glass.1.The text is especially helpful for those who care about _ _.A.their home comfortsB. their body shapeC. house buyingD. healthy diets2.A home environment in blue can help people ____.A. digest food betterB. reduce food intakeC. burn more caloriesD. regain their appetites3.What are people advised to do at mealtimes?A. Eat quickly.B. Play fast musicC. Use smaller spoonsD. Turn down the lights 4.What can be a suitable title for the text?A. Is Your House Making Y ou Fat?B. Ways of Serving DinnerC. Effects of Self-ConsciousnessD. Is Your Home Environment Relaxing?BGood Morning Britain's Susanna Reid is used to grilling guests on the sofa everymorning，but she is cooking up a storm in her latest role - showing families how to preparedelicious and nutritious meals on a tight budget.In Save Money: Good Food, she visits a different home each week and with the help of chef MattTebbutt offers top tips on how to reduce food waste, while preparing recipes for under ￡5per family a day. And the Good Morning Britain presenter says she's been able to put a lot ofwhat she's learnt into practice in her own home, preparing meals for sons, Sam, 14, Finn, 13,and Jack, 11.“We love Mexican churros so I buy them on my phone from my local Mexicantakeaway restaurant ,” she explains. “I pay￡5 for a portion( 份), but Matt makes them for26p a portion, because they are flour, water, sugar and oil. Everybody can buy takeawayfood, but sometimes we’re not aware how cheaply we can make this food ourselves.”The eight-part series(系列节目), Save money: Good Food , follows in the footsteps of ITV's Save Money：Good Health, which gave viewers advice on how to get value from the vast range of health products on the market.With food our biggest weekly household expense, Susanna and Matt spend time with a different family each week. In tonight's Easter special they come to the aid of a family in need of some delicious inspiration on a budget. The team transforms the family's long weekend of celebration with less expensive but still tasty recipes.5.What do we know about Susanna Reid？A. She enjoys embarrassing her guests.B. She has started a new programme.C. She dislikes working early in the morning.D. She has had a tight budget for her family.6.How does Matt Tebbutt help SusannaA. He buys cooking materials for her.B. He prepares food for her kids.C. He assists her in cooking matters.D. He invitesguest families for her. 7.What does the author intend to do in paragraph4？A. Summarize the previous paragraphs.B. Provide some advice for the readers.C. Add some background information.D. Introduce a new topic for discussion.8.What can be a suitable title for the text?A. Keeping Fit by Eating SmartB. Balancing Our Daily DietC. Making Yourself a Perfect ChefD. Cooking Well for Less第二节（共5小题，每小题2分，满分10分）根据短文内容，从短文后的选项中选出能填入空白处的最佳选项，选项中有两项为多余选项。

北师大版2019-2020学年三年级第二学期数学第五单元面积测试卷(含答案)

第五单元测试卷一、填一填。

(9～11题每空2分，其余每空1分，共27分)1．面积是1平方米的正方形，周长是()。

2．边长是()厘米的正方形的面积是1平方分米。

3．如右图所示，每个小方格的面积为1平方厘米，则阴影部分的面积是()。

4．一个长方形的长是5厘米，面积是20平方厘米，用它剪一个最大的正方形，则这个正方形的面积是()。

5．在括号里填上适当的单位名称。

一间教室的面积约是60()数学作业本封面面积约是4()体育场的面积约是2000()电脑键盘的面积约是8() 6．800平方分米＝()平方厘米()平方厘米＝20平方分米30000平方厘米＝()平方米()平方分米＝600平方厘米7．一根长8米的绳子正好绕方桌一周，这个方桌的面积是()。

8．边长是1分米的正方形，能分割成()个边长是1厘米的小正方形。

9．至少用()个边长是1厘米的小正方形，可以拼成一个大的正方形。

这个大正方形的面积是()，周长是()。

10．一个长方形镜子的面积为96平方分米，宽为8分米，它的长为( )。

11．一个长方形的宣传栏，长是3米，面积是6平方米，这个宣传栏的周长是()。

12．有一个69人的旅游团打算租车游玩，如果小客车15座，每辆租金120元，大客车28座，每辆租金150元，那么他们租()辆大客车，()辆小客车最划算，租金是()元。

二、判一判。

(每题1分，共4分)1．1平方米＞1米。

() 2．周长相等的长方形，它们的面积一定相等。

() 3．边长为16厘米的正方形纸可以剪成4个面积是2平方厘米的小正方形。

() 4．周长相等的长方形和正方形，正方形面积一定大。

()三、选一选。

(每题2分，共8分)1．一个长方形的宽是4厘米，长是宽的3倍，这个长方形的面积是()。

A．12平方厘米B．48平方厘米C．32平方厘米2．把一块长是16米，宽是8米的长方形菜地分成两块同样的正方形菜地，每块正方形菜地的面积是()。

A．24平方米B．64平方米C．132平方米3．用4个边长是1厘米的小正方形可以拼成一个长方形或一个大正方形(如下图)，它们的面积相比较，()，它们的周长相比较，()。

2019-2020学年度第二学期小学期末质量监测五年级试卷(含答案)

2019—2020学年度第二学期小学期末质量检测五年级数学试题（时间：60分钟）一、我会选（每题1分，共12分）1.比37大、比57小的分数有（）个。

A.1B.2C.3D.无数2.下列哪个数在数轴上最接近0.（）A.1B.- 12C.13D.-13.分子与分母相差1的分数一定是（）。

A.真分数B. 假分数C. 带分数D.最简分数4.把2米长的一根绳子对折3次，每段绳子占全长的（）。

A.13B.18C.28D.235.在23、35、58、74四个分数中，分数单位最大的（）。

A.23B.35C.58D.746.49的分子加上8，要使分数的大小不变，分母应该（）。

A.加上8B.乘8C.乘3D.不变7.下面各数中不能化成有限小数的是（）。

A.725B.1130C.516D.588.两个棱长1分米的小正方体拼成一个长方体，长方体的表面积是( )平方分米,体积是（）立方分米。

A.10，2B. 12，2C. 2,10D. 2,129.一辆卡车车厢的容积约是6（）。

A.立方米B.升C. 立方分米D.毫升10.至少用（）个小正方体才能拼成一个大正方体。

A.4B. 8C.16D.2711.下面四个图形中（每格都是正方形）不是正方体表面积展开图是（）。

A B C D12.将4个完全一样的长方体盒子用包装纸包成一包，已知每个长方体盒子的长是10厘米，宽是6厘米，高是1 厘米，下面4种包装方法，（）最省包装纸。

A B C D二、火眼金睛辨对错。

（每题1分，共10分）1.0℃表示没有温度。

( )2.最简分数的分子一定小于分母。

( )3.1千克的34相当于3千克的14。

( ) 4.真分数一定比1小，假分数一定比1大。

( )5.一根铁丝用去14，还剩34米。

( ) 6.体积相等的长方体，表面积一定相等。

( )7.分数单位相同的分数才能相加减。

( )8.所有非0自然数的公因数是1。

( )9.4个同学进行羽毛球比赛，每两人比赛一场，一共要比赛8场。

人教版2019-2020学年度第二学期期中教学质量评估六年级英语试卷及答案(含两套题)

2019－2020学年度第二学期期中教学质量评估六年级英语试卷测试时间: 60分钟总分: 100分题号听力部分笔试部分总分一二三四一二三四五六七得分听力部分（40分）一、听句子，选择你所听到的单词，每小题读两遍。

（10分）( ) 1. A. happy B. heavy C. heavier ( ) 2. A. taller B. smaller C. smarter ( ) 3. A. clean B. cleaner C. comic ( ) 4. A. on Sunday B. on Monday C. on Saturday ( ) 5. A. watched B. washed C. worried ( ) 6. A. book B. film C. room ( ) 7. A. than B. then C. they ( ) 8. A. thinner B. stronger C. longer ( ) 9. A. have a cold B. has a cold C. had a cold ( ) 10. A. better B. faster C. angry二、听句子，根据问题选择正确的图片，每小题读两遍。

（10分）( ) 1. Who is older? A. B.( ) 2. Which is longer? A. B.( ) 3. How big are Mike’s fe et? A. B.( ) 4. What did Amy do last night? A. B.( ) 5. What did Mike have for lunch? A. B.三、听对话，根据听到的问句，选择合适的答语，每小题读两遍。

（10分）( ) 1. What did Amy do?A. She did my homework.B. She watched TV.( ) 2. Was Sam’s weekend happy?A. No, it wasn’t.B. Yes, it was.( ) 3. How heavy is Jim?A. 51 kg.B. 52 kg.( ) 4. Who is taller?A. Sally is taller.B. Sally’s brother is taller. ( ) 5. What did John on Sunday?A. He played football.B. He saw a film.四、听短文，判断下列句子正误。

【精品试卷】2019-2020学年苏教版五年级下册数学试题-双周测

五年级数学下册第二周综合练习一、填空（每空2分，共24分）1、在①x+3.7=7、②a×2＞2.4、③5y+2y、④x=9、⑤2x+3y=9、⑥25×4=100、⑦15y=5x这些式子中，等式有（）；方程有（）。

(填序号)2、如果4x+1=8，那么2x+1=（）。

3、白羊有x只，黑羊是白羊的2倍还多10只，黑羊有（）只。

4、一个正方形的边长是a厘米，它的周长是（）厘米，面积是（）平方厘米。

当a=6时，面积是（）平方厘米。

5、已知△+△+△=75，○×△=100，☆÷○=120，则☆=（）。

6、在○里填上“﹤”、“﹥”或“﹦”（1）当x＝0.8时， x+14.6○15 12x○10.6（2）当x＝0.1时，0.5÷0.1○5 0.6x○0.5二、判断题（每题2分，共10分）1、2x+3y=18是等式不是方程。

（）2、x=8是方程27-1.7x=13.4的解。

（）3、若A+B=35，A+B+B=47，则B=12。

（）4、等式两边同时乘或除以一个小数，等式仍然成立。

（）5、等式左边加上一个数，右边减去同一个数，所得结果仍然是等式。

（）三、选择（每题2分，共6分）1、在2.9+x=2.9和2.9x=2.9这两个方程中，x的值（）。

A、相等B、不相等C、无法比较2、2a=3b（a、b为非0自然数），根据等式的性质，下面等式不成立的是（）。

A、12b=8aB、4a=9bC、20a=3b+18a3、已知3x=12，则4x-9等于（）。

A、27B、37C、7四、解方程（每题4分，共32分）15.8+x=62.9 2.5x=10 6.5+2.5x=7 48x-20=1241.9y+y=58 3x-1.7x=1.3 3.5y-2.5y=0.25 0.8y-1.9×3=3.3五、看图列方程，并解答。

(2x2=4分)（1）（2）六、先把数量关系填写完整，再列方程解答。

2019—2020学年度第二学期五年级期中检测

2019－2020学年度第二学期期中质量检测五年级数学试题一、口算（共10分）(1)3.9 ╳ 31 = (2) 5.4 + 10 = (3) 7.5 － 1.7 = (4) 12.56 + 4 = (5) 0.6 + 0.6 ╳ 99 = (6) 40 ╳ 3.14 = (7) 5.6 + 4 = (8) 224 – 99 = (9) 1 + 35% = (10) 50% + 30% = (11) 10 + 0.2 = (12) 875 + 125 = (13) 0.6 + 0.3 = (14) 0.4 ╳ 9 = (15) 40% ╳ 50 = (16) 9-3.17-4.83 = (17) 18 ╳ (21+65) = (18) 7 ╳ 3.14 = (19) 65 ╳152 = (20) 57╳ 35 = (21)3.14╳ 102 =(22) 0.2╳0.4 = (23) 30% ╳ 500 = (24) 3.14 ╳ 8 = (25) 3.6 ÷ 0.02 = (26) 12.56 ÷ 3.14 = (27) 0.09 ÷ 0.3 = (28) 0.05 ╳ 800 = (29) 25.12 ÷ 3.14 = (30) 12 ÷ 40% = (31) 23 ╳ 20% = (32) 2 – 0.08 = (33) 2.3 – 0.19 = (34) 108 ÷ (1+8%)= (35) 0.96 ÷ 2.4 = (36)48 ÷ 0.48 = (37) 14 ÷ 76 = (38) 0.42 = (39) 2.5 ╳ 8 = (40) 45 ╳ 20% =二、填空（每空1分，共22分）1.一个半圆形鱼池，直径10米，它的周长是（）米，占地面积是（）平方米。

2.15吨的40％是（）;15吨比10吨多（）％。