题干

1820年4月的一天,丹麦科学家奥斯特在上课时,无意中让通电导线靠近小磁针,突然发现小磁针偏转。这个现象并没有引起在场其他人的注意,而奥斯特却是个有心人,他非常兴奋,紧紧抓住这个现象,接连三个月深入地研究,反复做了几十次实验。关于奥斯特的实验,如图所示,下列操作中一定能够观察到小磁针偏转的是(   )

A: 通电导线AB东西放置,小磁针放在导线正下方,闭合开关

B:通电导线AB南北放置,小磁针放在导线正下方,闭合开关

C:通电导线AB东西放置,小磁针放在导线正下方,改变电流方向

D:通电导线AB南北放置,小磁针在AB延长线的B端外侧,改变电流大小

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B

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    There are plenty of beauty schools throughout the country that can help you to start a career in cosmetology(美容业). Nowadays, young people may not be able to afford a four-year college. Students can look forward to attending a beauty school program which will only take a few months to complete and start their career right away to earn money.

    There can be many benefits of going to beauty school. The expense is much less than attending a four-year university. Besides, attending beauty school is mostly a hands-on(动手的) experience which appeals to many people. Some students don't like sitting all day listening to lectures and then having to study at night. What's more, most beauty school programs keep up with the changing trends and fashion. So you will always be working on different hair types which can be fun and will give you a lot of experience throughout the years of your career.

    If you are worried about finding a job after graduation, many beauty schools will offer assistance for immediate job placement and give you peace of mind that you will not be stranded looking for a job. Most colleges and universities are not equipped to do that because of the large number of graduates each year.

    Cosmetologists will also make a good salary. The average salary will depend on your location, but you may earn a salary around $3,000--$3,500 a month. This is not including tips which could be $600 or more a month. Not only can young people go to cosmetology school, but people of all ages can start this career. As you can see, there are many benefits of beauty schools that can be the perfect opportunity for anyone to become a great cosmetologist.