①(3.2＋1.2)÷0.08
②0.4×(3.2－0.8)÷1.2
③0.75÷2.5÷0.4
④4.5×1.2－3.15÷15
⑤(7.5－2.3×0.4)÷0.01
⑥12.6÷3.6＋9÷3.6
