根据化学方程式4P+5O2
2P2O5，请写出它的三种读法： 点燃 .
①______．
②______．
③______．
从物质的名称方面可以读作：磷跟氧气点燃生成五氧化二磷．
从质量方面读作：每124份质量的磷可跟160份质量的氧气点燃生成284份质量的五氧化二磷．
从微观粒子方面读作：每4个磷原子可跟5个氧分子点燃生成2个五氧化二磷分子．
根据短文内容，从短文后的选项中选出适当的选项补全短文。 The earth is about 4,600 million years old. We humans have lived on the earth for only 35,000 years, but during this period we have changed our planet a lot in many ways. 1 All over the world, people have cut down millions of trees, so more and more kinds of animals and plants are disappearing. In big cities, cars and buses have polluted the air. Factories have also polluted the land and the water. 2 It is important to the earth. But now air pollution is destroying it and that has made a very big hole in the ozone layer (臭氧层). 3 This is very dangerous because it can cause cancer. Carbon dioxide (CO2) in the air has increased a lot. 4 it has formed a "blanket" (毛毯) around the each. 5 This makes our earth become warmer and warmer. Therefore, this causes the level of the ocean to rise. All these problems are very serious. We must do something to stop our earth from being polluted anymore.
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