气管镜可选用（）
A．干热灭菌
B．压力蒸汽灭菌
C．环氧乙烷灭菌
D．2%戊二醛浸泡灭菌
E．环氧乙烷灭菌或2%戊二醛浸泡灭菌
参考答案：E
The number of people in the party _____fifty, but a number of them ____ absent for different reasons. [ ]
A. were; was
B. was; was
C. was; were
D. were; were
封闭式熔断器是（）完全封闭在壳体内，没有电弧喷出，不会造成邻近带电部分飞弧和近处人员的危险。
A、导线
B、熔断丝
C、熔体
D、玻璃管
