A:①②
B:③④
C:①③
D:②④
历史课上,小敏和肖钢对于官渡之战的性质产生了疑问,请你帮他们从下面结论中,选出正确的一项( )
8500000平方米=____平方千米=____公顷
—Mum, I am hungry.
—Here is a for you. Why not help yourself to it?