×12= 2.5-1.7= 0.5×(2.6-2.4)=
2.2+3.57= 3.25×4= 0.9×(99+0.9)=
① = ②3.14×32= ③ = ④1÷50%=
⑤ = ⑥ = ⑦ = ⑧ =