能简算的用简便方法算．
9.28+1.82÷0.7        （71.2﹣71.2×0.9）÷0.25       6.5×2.3+6.5×6.7+6.5
7.8÷0.25÷4           1.37×99+1.37                  4.8×6.2﹣12.4．