条形磁体和通电螺线管之间有一小磁针，小磁针静止时北极的指向如图所示，请你标出电源的“+”“﹣”极，以及磁感线方向和条形磁体的S极

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—Which is more useful, reading or writing?

—I think _______ of them are useful.

    The Bamboo Train, or “Norry” in the local language, is quite famous in Cambodia. The train is in fact a big bamboo bed with four wheels and a small engine. It can run at the s____ of up to 50 km/h on the tracks. Lots of v____go to Cambodia to enjoy the Bamboo Train ride. They have to pay 5 dollars per person to g____on the train. The best time to take the train is from 4 to 6 o'clock in the afternoon, b____it is cool when people enjoy the countryside view. “It feels more like a roller coaster, but it's really nice,” a Germany tourist Theresa Kessemeier said after she c____a ride. The Bamboo Train has become a popular tourist at action.

如图，已知AB⊥GH，CD⊥GH，直线CD，EF，GH相交于一点O，若∠1=42°，则∠2等于（　　）