题目

听下面一段较长对话，回答以下小题。【1】Where does this conversation probably take place?A. In a restaurant. B. In an office. C. In a classroom.【2】Where does John do now?A. He’s a trainer. B. He’s a tour guide. C. He’s a college student.【3】How much can a new person earn for the first year?A. $10,500. B. $12,000. C. $15,000.【4】How many people will the woman hire?A. Four. B. Three. C. Two.在真空中上、下两个区域均为竖直向下的匀强电场，其电场线分布如图所示，有一带负电的微粒，从上边区域沿一条电场线以速度v匀速下落，并进入下边区域（该区域的电场足够广），在如图所示的速度--时间图象中，符合粒子在电场内运动情况的是（ ）A．B．C．D．