若单元体的应力状态为σx=σy=τxy,σz=τxy=τzx=0,则该单元的应力状态处于( )。
A.单向 B.双向C.三向 D.不能确定
参考答案:A
In our class, when the bell rang and the teacher closed his book, it was a for everyone to stand up.
A.signal
B.chance
C.mark
D.measure
下列不属于利用网络发布招募信息的优势的是( )
A.成本高 B.容量大 C.速度快 D.强调个性化服务