乙烯精馏塔塔压联锁时,下列动作正确的是()。
A.塔加热关闭
B.进料中断
C.塔顶停止采出
D.安全阀起跳
参考答案:A
He is also good at basketball and tennis _______ swimming. [ ]
A. except
B. besides
C. beside
D. but
疏散走道及其交叉口、拐弯处、安全出口处应设置疏散指示标志灯。疏散指示标志灯的间距不易过大,距地面高度应为()
A.1~2m
B.1.5~2m
C.1~1.8m
D.1~1.2m