正确答案: B

48%

题目：某小岛上原有果蝇20000只，其中基因型VV、Vv和vv的果蝇分别占15%、55%和30%。若此时从岛外入侵了2000只基因型为VV的果蝇，且所有果蝇均随机交配，则 代中V的基因频率约是

解析：

未入侵之前VV个体有3000，Vv个体11000，vv个体6000，入侵后VV变为3000+2000=5000，其它类型个体不变，但总数变为22000，则V基因频率为（5000×2+11000）/（22000×2）

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He had written some computer programs.

[单选题]ForthefirsttwoyearsinNewYork,theauthor_________.

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[单选题]

establish

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are dropped

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