①836-192÷8×16
②1.4÷(1.4+0.7)
③0.8×0.4×12.5×0.25
④ ÷6+ ÷20
⑤14×19×( + )
⑥ ÷[( + )÷ ]
301﹣81×35÷27 (52.05+5.1)÷9﹣2.9