题目

里氏震级M的计算公式为：M＝lgA－lgA0，其中A是测震仪记录的地震曲线的最大振幅，A0是相应的标准地震的振幅．假设在一次地震中，测震仪记录的最大振幅是1 000，此时标准地震的振幅为0.001，则此次地震的震级为________级；9级地震的最大振幅是5级地震最大振幅的________倍． 答案：6 10 000 [解析] 本题考查应用数学解决实际问题的能力． (1)M＝lg1 000－lg0.001＝3＋3＝6. (2)设9级、5级地震最大振幅分别为A9，A5，则9＝lgA9－lgA0,5＝lgA5－lgA0，两式相减得4＝lgA9－lgA5＝lg，即＝104，所以9级地震最大振幅是5级地震最大振幅的10000倍．A farmer carelessly lost an expensive gold watch in the barn on the farm, where he searched for everywhere but failed.So he put a notice on the gate of the farm: whoever finds the gold watch will be rewarded 100 dollars.People tried their best to look for the watch in order to get the reward. However, the barn was too large and the straw in the barn was too thick. It was getting dark and they were still unable to find it. So they gave up the reward of 100 dollars one by one.But only a small boy was still not discouraged but kept looking for it .He had nothing to eat throughout the day. In order to solve the family problem, he looked forward to finding the gold watch and let his parents, brothers and sisters have a full meal.The night was already getting late, the boy was also tired. He was lying in the straw to have a rest when he heard a strange “tick--tock ”.He immediately held his breath and listened carefully, and followed the sound. He found the watch and got the 100 dollars.Like the gold watch in the barn, success has been around us and spread in every corner of life. Only when we are calm and firmly look for it ,we can find it.1.If someone found the gold watch, what would the farmer offer him?A. 100 yuan. B. 100 dollars.C. 100 pounds. D. 100 pence.2.Why did the boy insist on looking for the gold watch?A. Because he liked the gold watch.B. Because he wanted to own the watch.C. Because he was silly.D. Because he wanted to get the reward.3.The passage above is probably taken from_________.A.A newspaper B.a science bookC. an advertisement D. a notice4.Which of the following is TRUE according to the passage?A. The boy had no brothers or sisters.B. The boy’s family had a hard life.C. It was easy for the boy to find the watch.D.The farmer didn’t look for the watch for himself5.Of the following,which order is right according to the story?① The boy succeeded in finding the gold watch② The farmer offered the boy a reward of 100 dollars③ A farmer lost a gold watch carelessly④ Many people tried to find the watch,but they failed.A. ②①④③ B. ④②③①C. ③④①② D. ①③④②