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vannanjthao
2 năm trước
vật A khối lượng 0.2 kg chuyển động với vận tóc 3 m/s đến va chạm của vật B khối lượng 0.1kg đang đứng trên một mặt phẳm nằm ngang động lượng của hệ trước va chạm là
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help me help me help me In biology and ecology the environment is all of the natural materials and living things on the Earth. This is also called the natural environment. Some people call themselves environmentalists. These people think that harmony with the environment is important. They think we must protect the environment. The important things in the environment that we value are called natural resources. For example fish, sunlight, and forests. These are renewable natural resources because they grow naturally when we use them. Non-renewable natural resources are important things in the environment that do not come back naturally. For example coal and natural gas. Câu 1: What does the world “environmentalists” in line 2 mean? 2 điểm A. people who protect the environment B. people who destroy the environment C. people who pollute the environment D. living things Câu 2: One example of renewable natural resource is_________. 2 điểm A. coal B. sunlight C. natural gas D. oil Câu 3: One example of non-renewable natural resource is_________. 2 điểm A. fish B. coal C. tree D. water Câu 4: All of the following things are renewable natural resources except_________. 2 điểm A. air B. gas C. silver D. animal Câu 5: What does the word “them” in line 6 refer to? 2 điểm A. environmentalists B. materials C. non-renewable natural resources D. renewable natural resources

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