本题目来源于试卷: Continuity and Change D.11 Stability & Change，类别为 IB生物学
[问答题]
1.Explain how limestone is made and describe od -6i7sc qas0the role10 c jf ylns6ztiw3l17 it plays in the carbon cycle.7 6zs3fyw i01 lnc1tlj
2.Oil and natural gas are extracted to be used as fuels. Describe the formation of oil and natural gas.
3.Nutrients are cycled in all ecosystems. Draw and label the carbon cycle showing at least four stores or sinks and at least four flows or processes.
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