油品中灰分是极少的，其测量原理主要是（）
A.蒸馏
B.蒸发和分解
C.灼烧
D.沉降分离
参考答案：C
— Could you tell me _____ and _____?
— Sure. [ ]
A. what's his name; how old is he
B. what his name is; how old was he
C. what his name is; how old he is
D. what was his name; how old was be
同正常绘制水位流量关系曲线，低水放大图绘制的标度比例也取（）的十、百、千的整数倍。
A、1
B、2
C、4
D、5
