甲醇的俗称是（）
A.酒精
B.木精
C.醋酸
D.石炭酸
参考答案：B
______ people have become masters of their country ____ science can really serve the people.
A．It is only then ;that
B．It is that;when
C．It is only when; that
D．It is when;when
简述烧结矿生产工艺？
