I like music that I can dance _____. [ ]
A. from
B. by
C. with
D. to
答案:D
已知多项式4x2m+1y-5x2y2-31x5y,
(1)求多项式中各项的系数和次数.
(2)若多项式是八次三项式,求m的值.
串联离心泵齿轮箱上方装有()。
A.活塞引水泵
B.真空泵
C.低压泵
D.水箱注水口