题目

阅读理解 阅读短文，根据短文内容，从每小题所给的A、B、C、三个选项中，选出最佳答案。 A well-dressed(衣着很好的) man goes into a restaurant one day. He sits down at a table near the window. A waiter comes up to him and says, “Can I help you, Sir?” The man says, “Yes, please. Can I see the menu(菜单)?” “Certainly,” answers the waiter. The man wants a good meal and he wants a lot of nice dishes. After a moment, the waiter brings them to him. The man is having his meal happily. At this time, a boy comes in and sits down beside the man. T17．如图所示，滑块以初速度v0开始沿表面粗糙且足够长的固定斜面下滑，直至速度为零，所用时间为t，对于该运动过程，若用x、v、a分别表示滑块的位移、末速度和加速度的大小，则下列表达式正确的是（　　）A．x=v0t+$\frac{1}{2}$at2B．v=v0+atC．x=$\frac{1}{2}$at2D．2ax=v0-v