Now comes word from Filmagazine , the most popular and best-selling film magazine , ______ 'Bodyguards and Assassins' (十月围城)--which combines historical drama and martial-arts wonder--won eight awards, including best film and best director for Teddy Chen.

A．that　

B．which

C．one

D．what

子弹射出时具有水平的初速度V₀=1000m/s，有五个等大的直径D=5cm的环悬挂着，枪口离环中心100m，且与第4个环心处在同一个水平线上，如图所示，（不计空气阻力）求：

（1）开枪同时，细线被火烧断，子弹能穿过第几个环？

（2）开枪前0.1s细线被烧断，子弹能穿过第几个环？