题目

When milk arrived on the doorstep When I was a boy growing up in New Jersey in the 1960s, we had a milkman delivering(投递) milk to our doorstep. His name was Mr.Basille .He wore a white cap and drove a white truck. As a 5 year-old boy, I couldn’t take my eyes off the coin changer fixed to his belt. He noticed this one day during a delivery and gave me a quarter out of his coin changer. Of course, he delivered more than milk. There was cheese, eggs and so on. If we needed to change our order my mother would pen a note-“Please add a bottle of buttermilk next delivery”-and place it小强家上半年的用水量是43.2吨，每吨水的价格是2.5元．小强家平均每月付水费多少元？