33=9 155=3 155=20
123=4 36=18 44=8
来源
食品包装袋
快餐盒
农用地膜
占“白色污染”总量的几分之几
+ = 1- = 1.25× = - =
0.9+99×0.9= 0÷ = 1÷ = -0.5=
0.6×101= 3.2×2.5×12.5=