废水处理装置是工厂各处流出的毒性或易燃物汇集的终点，应该置于工厂的（）。
参考答案：下风远程区域
物体所含______的多少叫质量．它的国际主单位是______，常用单位有______、______、______．
A number of foreign guests were invited to the party, but 20 of them didn’t___________.
A．turn up
B．break up
C．look up
D．make up
