Mary, Jane and May are very good friends. Mary is shorter than May, May is heavier than Jane. Jane is thinner than Mary. How old are they? Mary is 7 years old. Jane is 12 years old and May is 9 years old. They study at Qinglan Primary School. Mary likes English, Jane likes math and May likes music. They all study hard.

读我国地形示意图，回答下列各题：

数轴上一动点A向左移动2个单位长度到达点B，再向右移动6个单位长度到达点C，若点C表示的数为1，则点A表示的数为（　　）

由直线x=1，x=2，曲线y=sinx及x轴所围图形的面积为（　　）