题干
What does Bob want to do with Linda?
A：To go to the movies．
B：To play ping-pong．
C：To eat out．
答案(点此获取答案解析）
A
What does Bob want to do with Linda?
A：To go to the movies．
B：To play ping-pong．
C：To eat out．
。为使弹簧振子的振幅最大,则电动机的转速应为( )