题目

The welcoming library contains a wide range of up-to-date resources to support the learning and teaching needs of pupils and staff as well as their reading interests, encouraging students to become independent life-long learners.StaffLibrarian: Mrs PageLibrary Assistant: Mrs DuncanOpening Hours8:30 am – 4:15 pmThe library is open throughout intervals and lunchtime.ResourcesThe stock of about 8,000 items includes a wide selection of fiction to attract pupils of all ages and abilities. The non-fiction section contains items to help with homework and research, as well as plenty of books for gen如图所示：（1）用代数式表示图中阴影部分的面积（结果保留π）；（2）用计算器计算，当a=2.5，π取3.14时，求图中阴影部分的面积（结果保留3个有效数字）．