题干

直流电源跟一个线圈连接成闭合回路,线圈的上方和右侧各有一个可以自由转动的小磁针,它们静止时如图所示,则下列判断正确的是(   )

A:小磁针的c端为N极,电源的a端为正极

B:小磁针的c端为N极,电源的a端为负极

C:小磁针的d端为N极,电源的a端为正极

D:小磁针的d端为N极,电源的a端为负极

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D

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    For only the second time in her life, actress Olivia Holt, 15, traveled to New York---this time to catch the award—winning Disney Broadway show Newises. Adriana Palmieri, the reporter from Time for Kids(TFK),was there with Olivia and interviewed Olivia about the experience and her career. “I think the show is inspiring other people to make a big influence on the world today,” Olivia told TFK.

    Olivia is no stranger to the stage. This young star started acting at age three, and progressed from a small stage to a hit TV show, Disney XD's Kickin 'It. But even today she gets very nervous before each show. She overcame her nervousness by staying positive. “I end up just keeping my head up and seeing where it takes me and usually, it takes me to a good place where I'm not so nervous,” Olivia said.

    Olivia grew up in Mississippi but moved to Los Angeles recently to pursue her career. “It was a big transition for me because I grew up in a small town,” Olivia said. But now, she's living her dream as an actress. When asked about advice for other aspiring actors, the young performer said, “Just stay positive and stay confident. If you know that you're powerful enough to conquer your fears and stay happy, that will lead you in the right way.”

    Olivia regularly stars on a Disney XD show called Kickin'It. She plays the fearless black belt Kim. “I think she is such an incredible girl and I look up to her.” Olivia said about her character, “She is so powerful and confident.”