搜题请搜索小程序“爱下问搜题”
问题 单项选择题 A1/A2型题

60钴最大能量吸收发生在皮肤下（）

A.1cm处

B.2cm处

C.0.5cm处

D.2.5cm处

E.1.5cm处

答案

参考答案：C

解析：60钴最大能量吸收发生在皮肤下0.5cm处。

选择题

Robert Collier once said, “A single idea---the sudden flash of a thought

--- __________be worth a million dollars.”

A．should

B．may

C．must

D．will
查看答案
单项选择题

When whistle signals are used for launching lifeboats，one short blast means（）.

A.use the float-free method only

B.lower all boats

C.raise all boats

D.drill is over，secure all boats
查看答案