把小麦种子放在酒精灯上充分燃烧后剩下的灰分是（ ）
A．有机物
B．水分和无机物
C．无机盐
D．水分和有机物
答案：C
We ____ to be treated respectfully as we have been invited as honoured guests. [ ]
A. need
B. require
C. deserve
D. demand
—般来说，金融期货由于其标的物的特殊性都釆用现金交割方式。（）
