题目

有100kg汽油用去一半后，剩下汽油的A. 密度、比热容、热值都不变 B. 密度、比热容不变，热值减小一半C. 密度减小一半，比热容、热值不变 D. 密度、比热容、热值都减小一半 答案：【答案】A【解析】试题密度、比热容、热值都是物质的特性，不随物质的质量和体积的变化而变化．100kg汽油用去一半后，质量减半，体积减半，但剩下汽油的密度、比热、热值均不变．故选A．Kelly Reeves was getting ready for a trip when her phone slipped into a sink full of water. Panic moment! She quickly picked up the wet phone and tried to turn it on, but nothing worked. Her first reaction? She got dressed, drove to the nearest store, and bought a new model at full price. A new study finds that fear of losing your phone is a common illness. About 66 percent of those surveyed suffer from nomophobia or “no mobile phone phobia”. Interestingly, more women worry about losing their phone than men. Fortunately, there’s a solution. The first step is to figure out if you have nomophobia. Checking your phone too often is one thing, but the true sign of a problem is that you can’t conduct business or go about your routine when the fear becomes so severe. Do you go to unusual lengths to make sure you have your phone? That’s another sign of a problem. If you find you check your phone plenty of times per hour, or a total of an hour per day, there may be a problem. Some of the treatments are similar to those for treating anxiety attacks: Leaving the phone behind and not checking e-mail or text messages, and then learning to tolerate the after anxiety. Even if this leads to a high level of worry and stress, the solution is to push through the fear and learn to deal with not having your phone. Of course, there are also technological alternatives. Luis Levy, a co-founder at Novy PR,says he uses an application called Cerberus that can automatically track the location of his phone. To find it, he can just go to a Web site and see the phone’s location. He also insures his phone through a service called Asurion. The company’s description of its product reads like a prescription for anxiety: “60 million phones are lost, stolen or damaged each year. You’ll have complete peace of mind knowing that your phone is protected and you can quickly reconnect with family, friends and work, as soon as the very next day!” 64. Why does the author mention Kelly’s experience in the first paragraph? A. To introduce the topic for discussion. B. To inform us that mobile phones are useful. C. To warn us that we should be careful. D. To tell us we should get phones ready for a trip. 65. The underlined word “nomophobia” in Paragraph 2 means ________. A. Habits of using mobile phones.　　 B. Fear of losing mobile phones. C. Eagerness for new mobile phones.　 D. Independence of mobile phones. 66. Which of the following is a way to treat nomophobia? A. Avoiding using phone for some time B. Learning more about modern technology. C. Protecting one’s phone against any damage. D. Not using a mobile phone in one’s daily work. 67. Why can the service called Asurion help to treat nomophobia? A. It lets you know other people also lose their phones. B. It will give you a new phone through insurance. C. It enables you to reconnect with your acquaintance. D. It gives you a prescription to treat nomophobia. 68. What is the passage mainly about? A. Solutions to nomophobia.　　　 B. New mobile phone technology. C. Disadvantages of mobile phone.　 D. Attitude toward mobile phone.