钻井液循环系统安装和固控设备安装时,低压、中压管线分别用清水试压3Mpa,保持15分钟压力下降不超过()Mpa为合格。
A、0.02
B、0.05
C、0.5
D、0.1
参考答案:B
压力型手控定量气雾剂(MDI)给药后,药物在下呼吸道和肺泡的沉积率为()
A.30%
B.5%
C.20%
D.40%
E.9%~11%
The wise man exercises()in his behavior and enjoyments.
A.limitation
B.interest
C.restriction
D.restraint