题目

动词应用 根据短文内容，用括号内所给动词的适当形式填空，必要时可加助动词或情态动词。 My friend Peter was always having accidents. He did not pay attention to (注意) what he was doing or where he was going. A few months ago, a car    1   (hit) him when he went home from school. The driver was a bit tired, so he    2   (not see) Peter. At that time Peter was talking on his mobile phone and    3   (ride) in the middle of the road. The car ran into him. He broke his leg and was in hospital for over a month. Last week, he   4   (fal为了解人们对于国家新颁布的“生育二胎放开”政策的热度，现在某市进行调查，随机调查了50人，他们年龄的频数分布及支持“生育二胎”人数如表： 年龄[5，15）[15，25）[25，35）[35，45）[45，55）[55，65）频数510151055支持“生育二胎”4512821（1）由以上统计数据填下面2乘2列联表，并问是否有的99%把握认为以45岁为分界点对“生育二胎放开”政策的支持度有差异：（2）若对年龄在[5，15），[35，45）的被调查人中各随机选取两人进行调查，记选中的4人不支持“生育二胎”人数为ξ，求随机变量ξ的分布列及数学期望； 年龄不低于45岁的人数年龄低于45岁的人数合计支持a=c=不支持b=d=合计参考数据：P（K2≥k）0.0500.0100.001k3.8416.63510.828K2= ．