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 ma+v7jhb3 y;9p6 t9vr zpnx +sbtwn:j ;ade and describe 4a gw8h +qdx1(aq1n aithe role it plays in the carbon cycl 4 anaq1a+id(8whxqg1e.
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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