在横线里填上合适的计量单位.课桌抽屉的容积大约是15 .教室的占地面积大约是70 .
5:13==1.2: .
9÷ =0.6= :20=30: .
= :15==6÷ = (填小数)
:8=15÷ ==9: .
==12÷ = :20= (小数)