题干

已知∠α=55°34′,则∠α的余角等于____
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34°26′

同类题2

阅读理解

    Do you think you're green? You're a totally modern citizen, aren't you? You keep your bottles and take them to the bottle bank. You have a black bin and a green bin, one for general waste and one for recyclable waste. Your car uses lead—free petrol. You use the same plastic bag every time you go to the supermarket. Maybe you even cycle to work from time to time. You are playing your part; you are green and environment—friendly. Well, I've got news for you:

    YOU ARE NOT DOING ENOUGH!

    If you don't believe me, look at these facts. Trust me, they're from a BBC website.

    On average every person in the UK throws away their own body weight in rubbish every seven weeks.

    Every year, the average dustbin contains enough unused energy for 500 hot baths, 3,500 hot showers or 5,000 hours of television.

    Every UK household produces over one tonne of rubbish every year.

    If all the aluminium drink cans sold in the UK were recycled, there would be 14 million fewer full dustbins per year.

    Just one recycled aluminium can saves enough energy to run a television for three hours!

    At Christmas over 83 square kilometres of wrapping paper is thrown in the bin.

    Almost three billion nappies (used for baby) are thrown away in the UK every year. 90% of these are buried and take hundreds of years to disappear.

    Have I made you believe that you need to do more? No? OK, here are one or two more facts.

    Recycling just one plastic bottle saves enough energy to power a light bulb for six hours.

    Collecting dustbins and cleaning streets costs £1. 6 billion per year.

    Surely you must believe me now. You need to do more. The good news is that there is some— thing else you can do.

同类题3

阅读下面短文,请从每小题所给的A、B、C、D四个选项中选出最佳选项,并回答问题。

C

    Once upon a time,there was a king who had gone to visit neighboring kingdoms.He was gifted a pair of baby parrots by the king of the last kingdom where he was visiting.They were the most beautiful birds that he had ever seen.so,after returning to his kingdom,he called for a bird trainer and asked him to train parrots.

    The king also set up a place in the palace garden for the parrots.He often looked at them from his palace window.As time passed,one day the trainer came to the palace and told the king that though one of the parrots was flying high in the sky,the other one was not moving from its branch since the day it had arrived.

    When hearing this,the king summoned the best trainer from all his land and the nearby kingdoms.They came quickly and tried their best, but none of them could make the parrot fly!He even asked his courtiers to try to find a good way to make the parrot fly but they all failed.The parrot was not moving from his branch at all.Finally,after trying everything,the king thought to himself:"Perhaps I need someone who may be more familiar with natural habitat."He asked his courtier to get a farmer from the countryside and take him to the parrot to see if he could understand the problem with the parrot.

    The next morning,the king was surprised to see the parrot flying high above the palace gardens.He asked his servant to call that farmer to meet him.The servant quickly went and found the farmer.The farmer came and stood before the king.The king asked him,"How did you make the parrot fly?" With his hands folded with respect,the farmer said to the king,"It was very easy.I just cut the branch where the bird was sitting."