1. 0.012�0�5π×10/4=0.001131�9�3/s2. 3600×0.001131=4.07�9�3/h 1.8×4.07=7.326元(1)1s内从该水龙头流出0.001131立方米的水(2)1h浪费了4.07吨的水,若当地的水价为1.8元∕吨,则每小时用户要浪费7.326元钱水费