题目

(2015桂林)“全民阅读”深入人心,好读书,读好书,让人终身受益.为满足同学们的读书需求,学校图书馆准备到新华书店采购文学名著和动漫书两类图书.经了解,20本文学名著和40本动漫书共需1520元,20本文学名著比20本动漫书多440元(注:所采购的文学名著价格都一样,所采购的动漫书价格都一样).(1)求每本文学名著和动漫书各多少元?(2)若学校要求购买动漫书比文学名著多20本,动漫书和文学名著总数不低于72本,总费用不超过2000元If your mother told you to eat carrots so you’d be able to see in the dark, she was right. It turns out that feeding kids carrots is just one of a number of things to keep eyes healthy. Other things include regular eye exams, and sunglasses or hats are also very helpful, experts say.While eye disease is sometimes hereditary(遗传的), some are still preventable(可预防的), said Dr. Ron Weber, an Atlanta-based ophthalmologist. For example, nearsightedness, “not only has a genetic(基因的) component but is also influenced by how kids use their eyes during childhood,” he told Reuters Health by phone.He said that extended close work, such as reading, has long been thought to cause nearsightedness. Recent support has come from a study in which people with a higher level of education were more likely to have nearsightedness, because they spend more time reading or working on computers. Another study showed that children who spend more time outdoors are less likely to become nearsighted.But these findings don’t mean kids should be stopped from reading or working on the computer. Instead, Weber suggests, make sure a child’s environment is bright enough while they are doing close work. Parents should also help kids get into the habit of holding their reading material at the perfect distance – about 18 to 22 inches, he said. Finally, taking a break every five minutes or so, to let the eyes relax and focus on an object in the distance, will also help.One of the most important things a parent can do to help head off eye disease and vision problems is to make sure their child gets regular eye exams, beginning early in life. “The majority of vision problems in children are preventable and treatable,” said Dr. Ida Chung.1.What does the writer want to tell us in the passage?A. It is important to keep your eyes healthy.B. People seldom pay attention to eye health.C. It is necessary to give your kids carrots.D. All the eye disease are hereditary.2.Which one is good for our eye health according to the third paragraph?A. Spend more reading on computers.B. Spend more time indoors.C. Spend more time doing outdoor activities.D. Spend more time working on computers.3.The underlined part in the last paragraph means__________.A. treat B. stop C. cover D. increase4. Which can be the BEST title for this passage?A. Eating carrotsB. Eye diseaseC. How to keep eyes healthyD. The importance of eye health.
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