经审查重大件货物符合装运条件与要求后,需_。
A.编制配装图
B.编制吊装方案
C.编制衬垫方案和加固绑扎方案
D.计算重心位置
参考答案:A, B, C
Mary _______ her mother with the housework, but she didn’t.
A.must have helped
B.ought to have helped
C.must help
D.should help
施工单位应当根据不同施工阶段和周围环境及季节、气候的变化,在施工现场采取相应的安全施工措施。