对于炼油厂使用介质为烃类的换热器,其管程数一般在()管程之间。
A.2~4
B.4~8
C.6~8
D.2~8
参考答案:D
.Father is too busy to have any entertainments. If he __________me to go to the concert, I will be very glad.
A.promises
B.advises
C.suggests
D.agrees
他是个电影迷。