砌筑硝酸铵生产车间的承重墙体时，不得选用的材料是( )。
A．烧结空心砖
B．烧结多孔砖
C．蒸压灰砂砖
D．加气混凝土砌块
参考答案：C
鼓励合营企业向中国境外销售产品。( )
A. An equity joint venture shall encourage to market its products outside China.B. An equity joint venture shall be encouraged to marketing its products outside China.C. An equity joint venture shall encourage to market its products from outside China.D. An equity joint venture shall be encouraged to market its products outside China.
用盘形铣刀在铣床上铁削做螺旋槽，工作台应（）转动一个螺旋角。
