题干

【解析】A、海水中溶解有氯化钠等物质,所以海水的凝固点比水低.正确;

B、溶液和浊液特征的不同主要与物质分散在液体中的颗粒大小有关.正确;

C、一定温度下,物质的溶解度不随水的量的变化而变化.错误;

D、食盐水能导电是因为食盐水中含有较多自由移动的离子.正确。

故选C.

A:海水的凝固点比水低

B:溶液和浊液特征的不同主要与物质分散在液体中的颗粒大小有关

C:一定温度下,物质的溶解度随水的量的变化而变化

D:食盐水能导电是因为食盐水中含有较多自由移动的离子。

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C

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    There are many ways to find a job. It can be as easy as walking into a neighborhood store to look at its announcement(通告) board. Local stores often have areas where people can put small signs telling what kind of service they need or can provide. Such services include caring for children or cleaning houses.
    Or, job searchers can look in the newspaper. Local newspapers have employment announcements placed by companies seeking(寻找) workers.
Another popular tool for finding jobs is the Internet. For example, people in four hundred and fifty cities around the world can use the Craigslist(网站名)Web site to buy objects, meet people or find a job. Craigslist says that it receives two million new job listings each month.
Another useful way to find a job is through a college or university. For example, students at the University of Texas in Austin(奥斯丁 (美国得克萨斯州首府)) can go to the Career Exploration Center to get help in finding a job. Of course, looking for a job requires knowing what kind of work you want to do. For example, there is a book called “What Color is Your Parachute (降落伞)?” by Richard Bolles. This book has been helping people choose a career (职业) since it was first published in nineteen seventy.
    Some experts(专家) also help people find jobs. Susan W. Miller owns a company called California Career Services in Los Angeles. She says her company helps people find jobs by first helping them understand their strengths, goals and interests. Then she provides them with methods and resources(对策) to help them find the right job.

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Protect Children from Cyber-bullying

    When you think about bullying, you might think of a child being bullied by another in the schoolyard. As more young people have access to computers and cell phones, traditional bullying has gone digital, which has not yet gained awareness in Chinese parents.

    Cyber-bullying, first invented by Canadian educator Bill Belsey, is the use of the Internet and related technologies to harm other people, in an intentional, repeated, and unfriendly manner. It involves threatening text messages, the spread of online rumors on social networking sites, and intentionally keeping someone out of an online group. Cyber-bullying is at an all-time high in the US. According to a study from the US Department of Justice, more than 43% of teenagers report being victims(受害者)of cyber-bullying.

    Compared to face-to-face bullying, cyber-bullying is considered to have a worse emotional effect on the victims, and kids could feel more desperate and depressed. Severe, long-term or frequent cyber-bullying can leave victims at greater risk for anxiety, depression, and other disorders. Research says that cyber-bullying victims were almost twice as likely to have attempted suicide compared to youths who had not experienced it.

    In traditional schoolyard bullying, at least home is a safe place for the victims. But cyber-bullying is endless---it could happen anytime. Moreover, in the digital world, bullying is much easier, as a bully can pick on people with a much lower risk of being caught.

    Actually, cyber-bullying has become a worldwide issue. In the US, as several teens committed suicide because of cyber-bullying, some schools set rules to punish cyberbullies. Laws to punish cyber-bullying have been introduced in some states. In China, cyber-bullying is still considered by many parents and educators as a problem that involves physical contact. However, as cell phones and laptops are becoming common equipment for teenagers, social interactions have increasingly moved from personal contact to virtual contact. Cyber-bullying is spreading faster than expected.

    For schools and parents, safety rules should be set in the virtual world for kids, such as telling them not to let out anything to a stranger. Active steps should be taken to make the public aware of the seriousness of this problem, because it would be too late to take measures after tragedy strikes.