如图为中学实验室中常用的显微镜，请回答：

（1）使用显微镜对光的正确程序是：____ ．

①选遮光器上适宜的光圈对准通光孔 ②转动转换器，使物镜对准通光孔 ③左眼注视目镜（右眼睁开），转动反光镜调节出一个白亮的视野．

（2）观察时应先选用____ 物镜．（填“高倍”或“低倍”）

（3）显微镜下视野较暗，这时应转动____和____ 调节视野的亮度，如果物象不够清晰，调节____ 使物象更清晰．

（4）现有一台显微镜，它有两个目镜（放大倍数分别是5×和15×），两个物镜（放大倍数分别是10×和40×），那么这台显微镜的最大放大倍数是____ 倍．如果物像在视野的左下方，要使物像向视野中心移动，应将载玻片向____ 移动．

（5）视野中若有一个污点，擦拭目镜和移动装片时都不能移动，说明污点很可能在____上．

（6）在光线较暗时，应选用____ 面镜对着光源．

（7）将写有字母“P”的载玻片放在显微镜下观察，在视野中看到的图象是____ ．

    "Everything happens for the best." my mother said whenever things weren't going my way. "Don't worry. One day your luck will change."

    I found mom was right after I finished my college education. I had decided to try for a job in a radio station. I wanted to host a sports program one day. I went to Chicago and knocked at the door of every station. But I got turned down every time.

    In one station, a kind lady said my problem was that I hadn't got enough experience." Get some work in a small station and work your way up," she said.

    I went back home. I couldn't get a job there, either. I felt really down. "Your luck will change," Mom said to me. I tried another radio station in Iowa. But the owner told me he had already had someone. As I left his office, I asked, "How can someone be a sports announcer (播音员) if he can't get a job in a radio station?"

    I was waiting for the lift when I heard the man call. "What did you mean? Do you know anything about football?" He put me in front of a microphone and asked me to try to imagine that I was giving my opinion on a football game, I succeeded.

    On my way home, Mom's words came back to me," One day your luck will change, Son. And when it happens, you'll feel doubly good because of all the hard work you've had." At that moment I knew just what she meant.