今天全世界通用的纪年法是公元纪年，你知道这与传说中的哪一历史人物有关(    )       

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    July is coming. People all around the world are talking about their ____ (vacation). Parents would like ____ (help) their children relax. ____ (luck), they have two months off. Some people enjoy quiet life, so many of ____ (they) stay at home watching TV, using computers and so on. ____ some spend time differently. My pen pal Tony ____ blonde hair is a boy from the US. He says that ____ (America) like going to the countryside. Just like his big family, they often go to a farm. There, some can feed animals, some can play and ____ (other) can watch ____ nice sky and rivers. They can also taste delicious food. They are quite ____  (interest) in the life there.

假定五对等位基因自由组合，则杂交组合AaBBCcDDEe×AaBbCCddEe产生的子代中，有一对等位基因杂合、四对等位基因纯合的个体所占的比例是