餐饮单位杀灭虫害的方式，通常应首选（）。
A.器械
B.杀虫剂
C.灭鼠药
D.毒饵
参考答案：A
I sooner but I didn’t know that they were waiting for me.
A．had come
B．was coming
C．would come
D．would have come
细胞外液中主要的阳离子是
A．Na+
B．Fe2+
C．Ca+
D．K+
E．Mg2+
