A.
该应力状态的应力圆与τ轴相切,且σ1>0,σ2=0,σ3<0< /div>
B.
该应力状态的应力圆与τ轴相割,且σ1>0,σ2=0,σ3<0< /div>
C.
该应力状态的应力圆与τ轴相离,且σ1>0,σ2>0,σ3>0
D.
该应力状态的应力圆关于τ轴左右对称,且σ1>0,σ2=0,σ3<0< /div>
【简答题】第1章 课前翻译2 Dear Sirs , We are pleased to receive your E-mail of your catalogue on 24 May 2010. We are one of the largest importers of porcelain ware in Italy and wish to expand our present range with m...
【简答题】回文数是指从左到右与从右到左读都一样的.如22,,11,3443,94249等.显然2位回文数有9个:11,22,33…,99.3位回文数有90个:101,111,121,…,191,202,…,999.则: (1)4位回文数有( )个; (2)2n+1(n∈N+)位回文数有( )个。
【单选题】We are studying your offer and hope that it will remain till the end of credit payable by draft at sight.