大肠癌根治术后5年生存率为()
A.60%
B.50%
C.40%
D.30%
E.20%
参考答案:B
If I find his phone number,I ________ you.
A.tell
B.told
C.will tell
D.have told
断面平均流速v与断面上每一点的实际流速u的关系是()。
A.v=u
B.vC.v>u
D.v≤u或v≥u