题目

一个边形的内角和等于外角和的2倍，则其边数为______． 答案：【答案】6【解析】首先设边数为n，由题意得等量关系：内角和＝360°×3，根据等量关系列出方程，可解出n的值．解：设边数为n，由题意得：180（n﹣2）＝360×2，解得：n＝6，故答案为： 6．Hearing plays an important part in our everyday life, but few of us take the steps we need to protect our hearing.It is easy to see how your hearing is under assault in today’s world. There are so many things to hear, and so many new instruments, like iPods and headphones, which can harm your hearing if used improperly. Keeping the volume(音量)to a reasonable level on an iPod or other portable listening instruments is one of the most important ways to protect your hearing. Another great way to keep your hearing protected is to avoid loud noises whenever possible. There are many loud noises from power tools to machinery, and it is important to avoid these noises as often as possible. When it is not possible to avoid them, keep your hearing protected by using earplugs(耳机).If you think your hearing may have already been damaged by modern technology, it is important to have your hearing tested by a physician. Only such a professional will be able to measure your level of hearing loss and help you find the best solution to your hearing problem.For those with hearing issues, the choices have never been greater. There are many excellent hearing aids on the market. Having a hearing aid can be a perfect choice for the young and the old alike, and many people who swore they would never wear a hearing aid find that they love the convenience and quality these instruments represent.Never let an unimportant thing like vanity(虚荣) get in the way of treating a hearing problem. These days there are hearing aids that are nearly invisible to the naked eye, including a number of models that fit completely inside the ear. If you believe you may be experiencing a problem with your hearing, it is important to have it checked out, and to take the right measures to protect your ears. In many cases, this treatment will be as simple as wearing earplugs. Taking care of your ears is of great importance. After all, you only get one set of ears.                      【小题1】The second paragraph mainly talks about_____.A．the causes of hearing lossB．the importance of hearingC．how to cure hearing problemsD．how to protect your hearing【小题2】The underlined phrase “under assault” in Paragraph 2 most probably means_____.A．under considerationB．under protectionC．under attackD．under treatment【小题3】All the following factors may cause hearing problems EXCEPT_____.A．using iPods improperlyB．listening to MP3 at full volumeC．standing near machinery making a loud noiseD．using earplugs when there are loud noises