量一量下面平行四边形的四个角.∠1= ;∠2= ;∠3= ;∠4= .
= ÷ = %= 成= : .
==8÷ = (填小数)
= ÷32== ( 填小数)
== :1.6= %
× =÷ = %= :0.125=四成.