青枝骨折多发生在（） A.儿童 B.老年 C.中年 D.青年 E.以上都是

We had to walk home that night, tired , on account of , to our disappointment, __________．

A．there not being buses

B．there not having buses

C．there were no buses

D．there had no buses

The boy’s bad behavior at school __________ his mother many sleepless nights.

A．cost

B．made

C．caused

D．led to

常用研磨液有煤油、（）、10号与20号机油、工业用甘油、透平油及熟猪油等。

资金等值计算时，i和n为定值，下列等式中错误的是()。

A.(F/P,i,n)=(A/P,i,n)X(F/A,i,n)

B.(F/A,i,n)=(F/P,i,n)X(P/A,i,n)

C.(A/P,i,n)X(F/A,i,n)X(P/F,i,n)=l

D.(A/P,i,n)=(A/F,i,n)—i

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