1. (2024五上·房县期末)  脱式计算，能简算的要简算。

5.4＋4.6÷0.2           0.8×0.4×1.25×2.5              9.75÷1.5＋9.75÷2.5

8.9×10.1               3.6×6.5＋36×0.45－3.6