题目
Problem
The diagram shows a sector of a circle with centre and radius cm. The perpendicular bisector of passes through .
(a) Find the perimeter of the shaded region , giving your answer correct to 1 decimal place.
[4]
(b) Find the area of the shaded region , giving your answer correct to 1 decimal place.
[2]
题目中文翻译
图中显示一个圆心为 、半径为 cm 的扇形 。 的垂直平分线经过 。
(a) 求阴影区域 的周长，答案精确到 1 位小数。
(b) 求阴影区域 的面积，答案精确到 1 位小数。