题目

图中是物理教材中的两幅插图，甲图表示小铁球受磁铁的情况，说明力可以改变物体的 ；乙图是坐在船中的人用手推另一只船时，自己坐的船同时后退，说明物体间力的作用是。 答案：运动状态 相互创新阅读 Ways to Fall Asleep 　　为了尽快进入甜蜜的梦乡，历史上许多名人绞尽脑汁，有的人终于找到了自己独特的入眠方法，可有的人还是好梦难圆。你想探个究竟吗？ 　　How much sleep do we need? The answers are different. Some people need only three hours of sleep a night. Others need ten hours of sleep a night. Most Americans sleep for an average of seven to eight hours a night. After age fifty, the average sleep hours go down to 6.5 hours a night. 　　Most people will have a bad night when they can't fall asleep. About one in three Americans has a problem with sleep. Many of these people cannot fall asleep. The name of this problem is called insomnia（失眠症）. 　　This is not a new problem. Many famous people in history had insomnia. Some of these people had their own ways to sleep well. Benjamin Franklin （本杰明·富兰克林）, the famous inventor, had four beds. He moved from one to another to fall asleep. King Louis XIV（国王路易十四）of France had 413 beds and hoped to fall asleep in one of them. Mark Twain, the famous writer, had a different way: he lay on his side（侧卧）across the end of the bed! 根据短文内容，选择最佳答案。 (1)Most Americans usually sleep for about _______ hours a night. [　　] A．3 B．5～6 C．10 D．7～8 (2)As people grow older, they need _______ at night. [　　] A．less sleeping time B．more sleeping time C．the same amount of sleeping time D．a fixed time to sleep (3)If there are 100 million people in the US having a problem with sleep, what's the population of it? About ________. [　　] A．200 million B．300 million C．600 million D．900 million (4)Franklin tried to go to sleep by________. [　　] A．moving from one to another of his 413 beds B．moving from one to another of his 4 beds C．inventing a bed for himself D．lying on his side across the end of the bed (5)It's not mentioned in the passage, but we _________ know that Mark Twain was _______. [　　] A．a Frenchman B．an Englishman C．an American D．a German