答案:D
安全阀必须垂直安装,安全阀的阀座内径应大于( )mm;几个安全阀共同装设在一根与汽包相连的短管上时,短管通路截面积应大于所有几个安全阀门面积总和的( )倍。
A.25、1.25
B.25、25
C.1.25、25
D.1.25、1.25
I didn't have _____ to say, so I said _____.
[ ]
A. something; anything
B. anything; nothing
C. anything; something
D. nothing; something