一个圆锥底面积不变,高扩大2倍,它的体积就扩大6倍. (判断对错)
÷12=12: =75%═ 小数.
5÷8=== :64= %
÷8==0.5= %= : .
=0.25=4÷ = :28= %
12÷ ==== %= 折.