计算题：某高炉有效容积为1800m3，日产生铁3600t，求高炉的利用系数是多少t/

At the meeting they discussed three different _____ to the study of mathematics. [ ]

A. approaches

B. means

C. methods

D. ways

--- Do you doubt ____ he’ll be fired by the school?    

--- No, not a bit. But I doubt ____ he will bury himself into study.

A．that; that

B．whether; /

C．if ; that

D．that; whether

格拉夫卵泡颗粒细胞的营养来自（）

A.卵泡外膜

B.卵泡内膜

C.卵泡腔

D.卵丘

E.放射冠

慢性肾衰竭肾性骨病的病因为（）

A.代谢性酸中毒

B.铝中毒

C.骨化三醇缺乏

D.营养不良

E.继发性甲旁亢

货币乘数与货币供给的关系