回答下列有关生物进化的问题。
在一个种群中随机抽出一定数量的个体，其中基因型AA的个体占24%，基因型为Aa的个体占72%，基因型为aa的个体占4%，那么基因A的频率是（）；如果该种群足够大，虽然出现个体迁出现象，但是整个种群不存在基因突变，个体间也随机交配，自然选择也没有发生作用，那么该种群基因A的频率会不会改（）变？
参考答案：60%；会
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| One day, a train was approaching the small town of Cheekyville. On the train was a 1 man with a big suitcase, He was called William Warbler and he looked very 2 indeed. But what made him most unusual was the fact that whenever he needed to 3 , he did so by singing opera. Even if someone said "good day" to him, he would clear his throat and 4 : "Goood dayyy to youuuuuu to00000!"… Almost everyone considered William unusual, since no one could get a normal 5 word out of him. And, as no one knew how he made his living-and he lived quite 6 , always wearing his old second-hand suit-they often had no 7 for him and sometimes even made fun of him. William had been in Cheekyville for some years, when, one day, a rumor (谣言) 8 that William had 9 a role in a very important opera in the nation's capital, that there had been posters everywhere 10 the event, that nearly everyone in the capital had gone to see it, and that it had been a great 11 . And to everyone's surprise, when William was being 12 by reporters, he answered their questions by speaking 13 singing. And he did it with good 14 and with a clear and pleasant voice. From that day on, William 15 singing at all hours. He sang only during his stage appearances. Some people had an idea 16 he had changed, but others still had none, and continued believing him to be somewhat mad. They wouldn't have thought so 17 they had seen what William kept in his big suitcase. It was a large stone, with a hand-carved message on it. The message said: "Practice, my boy. Practice every second, for you never know when your 18 will come." Little did people 19 that he only got the role in the opera because the 20 had heard William singing while out buying a newspaper. | ||||
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