— It shouldn’t take long to clear up after the party if we all volunteer to help. 

— That’s right. __________.

A．Many hands make light work

B．Something is better than nothing

C．The more the merrier

D．The sooner begun, the sooner done

人耳分辨出前后两次声音的最短时间间隔是0.1s，如果你站在高墙边拍手，要听到拍手声被墙反射回来的声音，你与墙之间的距离至少应该是______m．