Hình tam giác ABCD ( AB// CD) có hai đường chéo AC và BD cắt nhau tại O. Gọi M,K,N,H lần lượt là chân đường vuông góc hạ từ O xuống các cạnh AB,BC,CD,DA.Chứng minh rằng:
a) OM/ON=AB/CD;
b)* OH/OK=BC/AD
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When people use something, ( something is glass bottles, paper – aluminum) we have 2 choices: the first, throw them in the trash and the second , recycle them. which is the solution you choose ?
If you choose the first solution, it means that : the aluminum will go into the landfill. That landfills are toxic and may be dangerous to the environment, because they are very hard to decomposed. It’s worth nothing that, recycling these objects means that their materials will be used again, reducing the need for cutting down trees or mining for materials to make cans. In addition, programs exist that pay people to recycle many of the things that they use, including aluminum cans, glass bottles, cell phones, and some types of scrap metal.
We can choose our solution to protect environment and our life, even small actions also contribute the big goal of human. Let‘s study some of ways to protect the environment and prace when you can, it’s just simple habit to implement in your everyday life which will make a difference.
We all want to protect our planet, but we’re mostly too busy or too lazy to put up big change that would improve our lifestyle and save the environment. Let’s change, we always have the chance to do it.
Environment is an essential part of our life. A clean environment is necessary for a peaceful and healthy life. An environment is the natural surroundings which helps human beings, animals and other living things to grow and develop naturally. But nowadays, our environment is disturbing in many different ways. Any type of disturbance in the nature’s balance affects the environment totally. It does not only ruin human lives but also affects on all living beings. We can save our environment with the little step taken by everyone on the earth. We should reduce the amount of waste, throwing wastes properly to its place only…and many other simple ways. It is very important to save environment for human existence. When we protect the environment, we are protecting ourselves and our future as well.