当栓索用以将吊臂顶部固栓于建筑物上,而承受吊索载荷的分力时,其安全系数应大于等于()。
A.8
B.7
C.6
参考答案:C
-Who’s that girl swimming in the pool? Is it Lucy?
-It be Lucy. She is sleeping in her bedroom now.
A.may
B.can’t
C.must
D.should
焦油加工的主要任务是获得酚、萘、蒽等纯产品和()等粗产品。