辐射管更换后,试验压力为()
A、3.0MPa
B、4.0MPa
C、6.0MPa
D、以上均错误
参考答案:C
西周法律规定,婚姻的缔结要经过六道程序,即“()”。
One of the biggest problems in food production has always been that people have no reliable access to exact information, ____________ is often the case in China.
A.that
B.what
C.which
D.it