+++ --
-+ -(-)
①[3.2×(1-)+3]×2
②
③×99
④3.75×4+1.6×3
⑤1÷2.5+2.5×0.4
⑥3-1-
①0.53×2.5+
②25×0.032×12.5
③ [()×]
④6.83+17.9﹣0.83+32.1
①8×2.5×0.125÷
②(+﹣)×24
③6.5÷×
④(+)×+
⑤4×(﹣)×9
⑥÷7+×