题目

市和市分别有库存的某联合收割机12台和6台，现决定开往市10台和市8台，已知从市开往市、市的油料费分别为每台400元和800元，从市开往市和市的油料费分别为每台300元和500元． （1）设市运往市的联合收割机为台，求运费关于的函数关系式． （2）若总运费不超过9000元，问有几种调运方案？ （3）求出总运费最低的调运方案，并求出最低运费． 阅读理解 　　People bury treasure to stop other people from taking it．They choose a quiet place, dig a deep hole and bury the treasure in it．Then they make a map of where the treasure is or write down other clues(线索)that will help them or someone else to find it again． 　　In Britain a few years ago, a writer wrote about some treasure that he had buried．He put clues in the story to help readers find it．Thousands of people hunted for the treasure．They dug holes all over Britain, hoping to find it． 　　One of the most popular adventure stories ever written is Robert Louis Stephenson's “Treasured Island”, an exciting story about a young boy, Jim Hawkins, who is captured by pirates(海盗)and later finds some buried treasure． 　　Then there is the true story about a man who had to travel overseas for a year．He did not trust banks, so he buried his life savings in a park．Then he went away．On his return, he went straight to the park．But the park was no longer there．In its place there was a huge building． 　　And then there was the man who buried his savings, all in bank notes, in a waterproof(防水的)bag．When he dug it up years later, there was nothing left．Worms and insects had eaten the bag and everything in it． 　　And of course, these are stories about people who bury things and either forget where they have buried them or lose the map． 　　Although it is true that people sometimes lose their money because a bank fails, banks are still the safest place to keep our savings and treasures． (1) People who bury treasure usually ________． [　　] A． do not trust banks B． have a little money． C． want to live in a quiet place． D． expect to lose it (2) The writer in Britain ________． [　　] A． really had buried something． B． started a nationwide treasure hunt． C． had lost his treasure and wanted people to help him find it． D． caused trouble because people dug holes everywhere． (3) “Treasure Island” ________． [　　] A． is a story about pirates． B． is about the adventures of Jim Hawkins． C． is the most popular story ever written． D． is a well-known fairy tale． (4) The man who buried his money in a park _________． [　　] A． thought his money was safer there than in a bank． B． travelled on the sea for a year． C． got his life savings back again． D． stayed away longer than he expected． (5) From these stories we understand that _________． [　　] A． we cannot trust banks． B． we should not trust anyone． C． a waterproof bag is not proof against worms and insects． D． insects eat anything．