已知.把A、B、C、D、E这五个数从小到大排列,第二个数是 .
20: =0.8==24÷ = %.
=8÷ = :20=0.25.
=15÷ = ÷30=七五折= %
6: == %= ÷32.
1.5=18÷ == :6= %