I eat dinner ____________ my family. [ ]
A. and
B. with
C. for
答案:B
外源的重组体与感受态细胞混合后,一般在何种温度下作短暂的热刺激?()
A.37℃
B.42℃
C.55℃
D.72℃
E.95℃
变量泵调速采用的是()。