— do you go to work?
— By bike.[ ]
A. How
B. What
C. Why
D. Which
答案：A
心肺复苏时最常用的首选药是
A．利多卡因B．肾上腺素C．异丙肾上腺素D．去甲肾上腺素E．阿托品
如何区分熔焊和钎焊？二者各有什么特点？
