用于要求严谨,需要记录备案的沟通方式为?()
A.口头
B.书面和非语言
C.电话
D.传真
参考答案:B
3′末端具有CCA-OH的RNA是
A.rRNAB.mRNAC.tRNAD.hnRNA
My father has worked there ___________.
A.since five year
B.since 1990
C.for five years ago
D.five years