题目

Let's Go Fly a Kite...?at Piedmont Middle School's celebration of kites!Come and learn how to build all sorts of kites, from the simplest diamond-shaped kites to the most complex box kites. Stay as long as you like and build as many kites as you want. Once you have finished a kite, get advice on flying techniques from kite expert Lorena Hallsberg. The celebration will be at Piedmont Middle School, 151 Piedmont School Drive.The Piedmont Middle School Parent Teacher Organization (PTO) has organized a refreshment(茶点) tent. All profits will benefit future PTO activities. Take a break from kite在Rt△ABC中，∠C＝90°，AB＝17，BC＝8，则AC的长为A.15B.14C.13D.12