质量为M的小车以速度v0在光滑水平面上匀速运动,车上另有两个质量皆为m的小球a和

题型:选择题

问题:

质量为M的小车以速度v0在光滑水平面上匀速运动,车上另有两个质量皆为m的小球a和b。现分别将小球a和b沿水平方向以速率v(相对地面)向前和向后抛出。抛出两小球后小车的速度是   

A.0

B.v0

C.

D.

考点:动量守恒定律
题型:选择题

下列关于SARS病毒所含核酸的叙述,说法正确的是 [ ]

A.含有A、G、C、T四种碱基,五碳糖为核糖 

B.含有A、G、C、U四种碱基,五碳糖为脱氧核糖

C.含有A、G、C、T四种碱基,五碳糖为脱氧核糖 

D.含有A、G、C、U四种碱基,五碳糖为核糖

题型:选择题

写出下列各数.

三十八万四千二百五十一写作:______

五亿零九十万三千七百八十写作:______

五百亿三千万六千写作:______.

题型:选择题

—I failed the maths test.   

—___________[ ]

A. I'm sorry to hear that.                 

B. It doesn't matter.                 

C. Take it easy.

题型:选择题

第三部分 阅读理解

(共15小题,每题2分,满分30分)

Cheating can happen in a lot of different ways. When people cheat, it’s not fair to other people, like the kids who studied for the test or who were the true winners of a game.

Many people like the action of cheating. It makes difficult things seem easy, like getting all the right answers on the test. But it doesn’t solve the problem of not knowing the material and it won’t help on the next test --- unless the person cheats again.

Some people lose respect for cheaters and think less of them. The cheaters themselves may feel bad because they know they are not really earning that good grade. And, if they get caught cheating, they will be in trouble at school, and maybe at home, too.

Some kids cheat because they’re busy or lazy and they want to get good grades without spending the time studying. Other kids might feel like they can’t pass the test without cheating. Even when there seems to be a “good reason” for cheating, cheating isn’t a good idea.

If you were sick or upset about something the night before and couldn’t study, it would be better to talk with the teacher about this. And if you don’t have enough time to study for a test because of swim practice, you need to talk with your parents about how to balance swimming and school.

A kid who thinks cheating is the only way to pass a test needs to talk with the teacher and his or her parents so they can find some solutions(解决办法) together. Talking about these problems and working them out will feel better than cheating.

56.The author thinks that when kids cheat in class, _______.

A.it is unfair to other people    B.it does harm to their heath

C.teachers should punish them  D.teachers shouldn’t stop them at once

57.Some students like cheating mainly because_________.

A.the material in the test is very difficult

B.they want to do better than the others

C.cheating can make hard things seem very easy

D.they have little time to study their lessons

58.The fourth paragraph mainly tells us______.

A.cheating isn’t a good idea   B.why kids cheat in the test

C.some kids can’t pass the test without cheating

D.some kids don’t spend the time studying

59.We can learn from the passage______.

A.cheaters are often thought highly of

B.people show no respect for those who cheat

C.parents whose kids cheat are often in trouble

D.kids cheat in the test because of swim practice

60.In the passage those cheaters are advised to_______.

A.spend more time on school than on sports

B.find good solutions instead of cheating

C.try hard to be intelligent rather than lazy

D.ask their classmates for good methods of study

题型:选择题

社稷

更多题库