一个物体只受两个力的作用，且这两个力的三要素完全相同，那么（_爱下问搜题

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问题选择题

一个物体只受两个力的作用，且这两个力的三要素完全相同，那么（　　）

A．物体所受的合力可能为零

B．物体的运动状态可能保持不变

C．物体的运动状态一定改变

D．物体所受合力一定为零

答案

答案：C

选择题

设a、b、c、d均为负有理数，则下列不等式不成立的是（　　）

填空题

选词填空。根据短文内容，从方框中选择适当的选项完成短文。（有两个选项是多余的）（10分）

A. to plan B. mountains C. money D. One E. history F. called
G. holiday H. pay I. any J. tickets K. to get L. everything

Many people like traveling. They go to the 小题1: , the seaside or forests. Some people like 小题2: , so they like to visit some old interesting places. In many countries, the travel agencies can help you 小题3: your holiday. You can tell the travel agency what kind of 小题4: you like and how much 小题5: you want to spend and the travel agency will give you a lot of information about where to go, how 小题6: there, where to stay, and what kind of activities you can do there. 小题7: of the ways of travel is 小题8: “package” travel.
That is, you just 小题9: the money. And the travel agency will plan 小题10: for you, including the ticket for the train or plane, the hotel, the activities and so on.