Ten minutes later, I was twenty dollars poorer, and the bookshelf was tied on the roof-rack.
十分钟后，我又少了20美元，这个书架被我绑在车顶行李架上。
2
It USES radar and optical sensors to calculate the trajectory of an incoming warhead, and then intercepts it with a projectile fired from a roof-rack (pictured).
它利用雷达和光学传感器来计算出入弹的道弹的轨迹，然后从一车顶架(图)发射出射弹去拦截导弹。
3
Load canisters of it on the Grand Cherokee's available roofrack and you won't need to stop for gas.