题目

During the summer holidays there will be a revised(修改过的)schedule of services for the students. Changes for dinning-room and library service hours and for bus schedules will be posted on the wall outside of the dining-hall．Weekly film and concert schedules, which are being arranged(安排), will be posted each Wednesday outside of the student club.In the summer holidays, buses going to the town center will leave the main hall every hour on the half hour during the day．The dining-room will serve three meals a day from 7:00 am to 7:00 pm during the week and two meals from noon to雪灾是由于大量降雪与积雪对人们的生产和生活造成危害和损失的一种气象 灾害。据此回答 （1）下图表示“寒潮—大风—雪灾”灾害链。读图并将下列选项前的字母填在与图中数码相应的空格内。( 8分 )A．雪灾    B．低温   C．垮堤坝    D．生物冻害   E．大气污染①        ②        ，③________,④      ，⑤      。（2）2008年1月至2月，我国南方遭遇了强度大、持续时间长的罕见雪灾。读中国部分地区一月平均气温图，回答：此次雪灾期间，A省与其东部纬度更低的B、C、D、E、F等省不同，没有出现严重雪灾。请根据我国部分地区一月平均气温分布特征和所学知识，简要说明原因。