英雄连勇气传说

编程分段计算居民水费

```python 水费计算程序def calculate_water_bill(units): if units ˂= 10: return units * 7.5 elif 10 ˂ units ˂= 20: return 10 * 7.5 (units 10) * 9 elif units ˃ 20: return 10 * 7.5 10 * 9 (units 20) * 12 输入用水量usage = int(input("请输入本...