5．脱式计算，能简算的要简算：
0 163874 163882 163888 163892 163898 163900 163904 163910 163912 163918 163924 163928 163930 163934 163940 163942 163948 163952 163954 163958 163960 163964 163966 163968 163969 163970 163972 163973 163974 163976 163978 163982 163984 163988 163990 163994 164000 164002 164008 164012 164014 164018 164024 164030 164032 164038 164042 164044 164050 164054 164060 164068 199269
| （455-12.5×4）÷8.1 | 39÷0.125÷0.8 | 12.7+12.5÷5 |
| （7.5-2.3×0.4）÷0.01 | 2.16÷0.9÷0.3 | 78÷0.25÷0.4． |