The suggestion that the meeting _________requires _________.

A．puts off; being considered

B．be put off; to be considered

C．should be put off; considered

D．is put off; being considered

火车紧急刹车后经7s停止，设火车匀减速直线运动，它在最后1s内的位移是2m，则火车在刹车过程中通过的位移（）m和开始刹车时的速度各是（）m/s。