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Is Tom at school today?No, He ’s at home ______ he has a bad cold.

更新时间:2024-11-24 04:47:38
A、because
B、if
C、until
D、before
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正确答案:

A

答案解析:

暂无解析

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[B]Describinghowgrowthratesinnaturalpopulationsfluctuateovertimeandexplainingwhythesechangesoccur.

[C]Proposingahypothesisconcerningpopulationsizeandsuggestingwaystotestit.

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[B]Advocatemorerigorousstudyofdensity-dependentfactorsinpopulationgrowth.

[C]Provethatthedeathratesofanypopulationareneverentirelydensity-independent.

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[C]Presentconceptualcategoriesusedbyotherbiologists.

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