CR四象限理论中,第四象限对应的曲线为()
A.照片特性曲线
B.增感屏特性曲线
C.IP特性曲线
D.光激励荧光物的特性曲线
E.FPD特性曲线
参考答案:A
Mr. Li will go to Guangzhou by air. His workmates are ______ at the airport.
A.turning him off
B.seeing him off
C.taking him off
D.putting him off
继发性自发性气胸最常见的病因是()
A.COPD
B.支气管肺癌
C.肺结核
D.尘肺