你能求未知数x的．①0.4×（x-1.5）=1.6②16：34=x：94．

几乎无肾脏毒性的头孢菌素是

A．头孢匹罗

B．头孢噬吩

C．头孢孟多

D．头孢他啶

E．头孢氨苄

斗轮机运行时，遇到机器故障时，先汇报班长，再停机。

食品工业是否可以杜绝使用食品添加剂？为什么？

As an extinguishing agent，foam（）.

A.conducts electricity

B.should be directed at the base of the fire

C.is most effective on burning gases which are flowing

D.extinguishes by cooling oil fires below ignition temperature

抗"O"实验大于800的临床意义。