题干

水是一种资源,也是一种能源.古代劳动人民巧妙地利用水来开山采石;冬季,在白天给石头打一个洞,再往洞里灌满水并封实,待晚上降温,水结冰后石头就裂开了(冰的密度比水的小).下列有关说法正确的是

A:石头裂开后密度减小

B:石头裂开后密度增大

C:该方法利用水结冰后质量变大,体积增大而使石头裂开

D:该方法利用水结冰后质量不变,体积增大而使石头裂开

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D

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    What happened to that brilliant idea that you once had? Did you ignore it because you thought that it was just a little thought? Have you ever considered what that little thought would have become if you had acted on your instincts(本能) or if you had paid more attention to it?

    Imagine a scene, where you are sitting at home watching television or reading a book, suddenly a light bulb is turned on in the dark tunnel of your mind as a thought or an idea crosses your mind. The thought catches your attention but seems so meaningless and you are tempted to abandon it, but wait a minute!

    That thought could be the potential beginning of the success you have so much wished for. As the thought crosses your mind, your senses become alert and you suddenly see a possibility, a solution, or find the answer to a problem whose solution has long escaped you.

    It is almost as if a wise man has whispered the perfect solution into your ear or awakened your senses to a reality, thereby bringing light to your life. It is like finding the last piece of jigsaw puzzle(拼图游戏). This becomes an amazing moment and everything freezes around you as you excitedly try to grasp the practicality of that little but powerful thought.

    Your self-confidence and enthusiasm increase as you become conscious of the great possibilities that can arise if that little thought is acted upon. This becomes the moment to build upon that thought and to put down any ideas that are streaming from that little thought for later review.

    Seemingly meaningless little thoughts or ideas when acted upon have a potential to explode into great projects.

    Many successful projects have been born from the little positive thoughts that were carefully protected and recognized as tickets to great things.

You may have heard people say many times that it just came to me in a flash moment, a small idea or seemingly meaningless thought may cross your mind about something you have been planning to accomplish.

    Don't waste an opportunity to act on a potentially brilliant idea. You don't have to wait for a major idea, or approval from your peers in order for you to act on that little thought. That little thought or idea is the beginning of great things if you decide to follow it through.