SCIENCE STUDY
How do trees help us live better?
你每年需要消耗多少氧气？
It takes about 7 to 8 trees to make enough oxygen (氧气) for one person to breathe for a year.
The average person needs around 700–800 kilograms of oxygen per year. A large tree might make around 100 kilograms of oxygen per year. TEENS
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