喷射混凝土和喷浆支护可以起到()作用。
A.结构
B.充填
C.悬吊
D.隔绝
E.柔性支护
参考答案:A, B, D, E
内部收益率的定义是什么?两种定义法有什么区别和联系?各自适用于什么场合?
35. —Hey, Kelin. Happy new year! ______?
—Ok, I guess. My grandma kept cooking and cooking, so I just kept eating.
A.How was your break
B.How is your grandma
C.Where did you go for holiday
D.What did you do in your holiday