液压泵的型号为CB-B50,代表的名称是(),额定流量是50r/min。
A、齿轮泵
B、叶片泵
C、柱塞泵
D、往复泵
参考答案:A
转氨酶的辅酶中含有的维生素是()
A.维生素B6
B.维生素B1
C.维生素B12
D.维生素B2
E.维生素C
Those books are yours, and the rest _____ mine. [ ]
A. is
B. are
C. was
D. were