题目

Memory, they say, is a matter of practice and exercise. If you have the wish and really make a conscious effort, then you can quite easily improve your ability to remember things. But even if you are successful，there are times when your memory seems to play tricks on you.Sometimes you remember things that really did not happen. One morning last week, for example, I got up and found that I had left the front door unlocked all night, yet I clearly remember locking it carefully the night before.Memory “tricks work the other way as well. Once in a while, you remember not doing something, and t为了保护环境，某企业决定购买10台污水处理设备．现有A、B两种型号设备，且A、B两种型号设备的价格分别为每台15万元、12万元．经预算，该企业购买设备的资金不超过130万元．（1）请你设计，该企业有几种购买方案；（2）A、B两种型号设备每台一个月处理污水量分别为250吨、220吨．若企业每月产生的污水量为2260吨，为了尽可能节省资金，应选择哪种购买方案？