He loves keeping his own opinion to himself.
苯扎溴胺溶液泡手的浓度是
A. 0.01%
B. 0.1%
C. 0.2%
D. 1%
E. 2%
下述哪类物品不宜高压蒸气灭菌的物品是
A. 锐利器械
B. 玻璃类
C. 敷料类
D. 橡胶类
E. 搪瓷类
The reason why the water in this area had been polluted was the ______ (poison) substances had been poured into the river.