题目

请先阅读下面短文，掌握其大意，然后根据短文内容从下面方框内的七个选项中选择五个还原到文中，是短文意思通顺、结构完整，并在答题卡上将其序号涂黑。I live in a small town near Xing'an in Guilin.【1】 , because it is too small. The air here is fresh（清新的）. There are not many tall buildings in our town.【2】. There are four hundred students and twenty-five teachers in our school. In the front of the school, there is a playground.【3】 There is a little garden behind our school. And we can grow beautiful flowers and p一个学生估算一块木头下面鼠妇的种群数量。她捉了40只鼠妇，将它们标记后放回，并与该 种群中的其他个体混合在一起。20h后，她又捉了40只鼠妇，在新捉的鼠妇中， 只有16只是有标记的。假定在20h内，鼠妇无死亡，没有受伤害，无迁入与迁出，则鼠妇的种群数量为（   ） A.60只  B.100只  C.80只  D.无法确定