Problem: Given the question: What is the missing first step of the following process: - These plants die - The soil gains organic material - The soil becomes more fertile - Larger plants are able to be supported - Trees eventually grow.
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The answer is:
Grass and small plants grow in an area

Problem: Given the question: What is the missing first step of the following process: - People burn coal for heat or electricity - Pollution from the coal goes into the sky - Coal pollution enters clouds - Clouds rain over an area - The polluted rain becomes acid rain.
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The answer is:
People dig up coal from the ground

Problem: Given the question: What is the missing first step of the following process: - The oxygen travels to the lungs through the windpipe - The air sacs in the lungs send the oxygen into the blood stream - The carbon dioxide in the blood stream is transferred to the air sacs - The lungs expel through the nose or mouth back into the environment.
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The answer is:
You breathe oxygen into your body through the nose or mouth