题目

In some western countries，children _________ school and _________ home at three o'clock in the afternoon． A．start，go             B．starts，goes           C．finish，go            D．finishes，goes 答案：C物体做初速度为2m/s、加速度为 2m/s2的匀加速直线运动，求（1）物体在第2s 末的速度；（2）物体在第2s 内位移．