天然辐射源对全世界人类照射的人均年有效剂量水平的范围是
A.<1mSvB.1~3mSvC.3~5mSvD.5~10mSvE.>10mSv
参考答案:B
—Hello, is that Lisa speaking?
—Yes, .[ ]
A. Who are you?
B. I'm Lisa.
C. Who's that?
D. I'm speaking.
诱发或加重心力衰竭的因素中最常见是
A.呼吸道感染
B.身心劳累
C.循环血容量增加或锐减
D.严重心律失常
E.治疗不当