His aunt’s letters him of those beautiful days when they used to live together in his hometown. A. call up B.call for C.call on D.call at 答案:A 解析: call up:想起某事物.回忆某事,call for:需求.需要,call on:号召.请求拜访(某人),call at:拜访(某地)。他婶婶的信使他想起了他们在一起度过的日子,故选A。函数y=2(x﹣4)2+5的顶点坐标为 .