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How to become a radio DJ

  Do you have a great voice? Have you ever thought l about becoming a radio DJ? Working as a DJ can be exciting but it also needs experience．If you want to be a DJ，the following are usual ways to start .

     1. Intern(实习)．It's a dirty job．Unluckily，most radio station workers start as an intern．This means working long hours without pay．It will help you do better at the radio station．   

    2. Events．Because you can't get a DJ job with no experience，you might want to work as a DJ for events. Weddings，parties and special situations all need DJs to  provide the music and some laughs．This is a great way to learn to work with people and play music．

    3.Fill in(替补)．If you work at a radio station，you can ask to be put on the ‘‘ fill in ” list for DJs．So if the main DJ gets sick，you can fill in for him or her to get some experience．

    4.Late，late night．Usually the first job for a DJ is the late shift(晚班)．In other words you may be on air not only from l a．m．to 5 a．m．，but you will get more experience·

已知圆O：x²+y²=4，圆O与x轴交于A，B两点，过点B的圆的切线为l，P是圆上异于A，B的一点，PH垂直于x轴，垂足为H，E是PH的中点，延长AP，AE分别交l于F，C．

（1）若点P（1，$\sqrt{3}$），求以FB为直径的圆的方程，并判断P是否在圆上；

（2）当P在圆上运动时，证明：直线PC恒与圆O相切．