已知单代号网络计划中某工作ES=4d,EF=6d,LS=7d,LF=9d,则该工作的总时差为()d。
A.2
B.3
C.4
D.5
参考答案:B
— Mom, may I play computer games just for a while?
— ________!Dad is writing his paper.[ ]
A. Help yourself
B. It's up to you
C. Behave yourself
D. Go ahead
()时的电源故障可能会丢失未保存的数据。