How would you deal with the problem? How about asking our teacher for help?
A：mind
B：solve
C：expect
在△ABC中，角A,B,C所对的边分别为a,b,c，若a=7,b=5,c=8，则△ABC的面积S等于（ ）
国家图书馆建馆100年来，积极服务于广大读者，见证了国人读书的历程和变化，为我国社会文明进步作出了巨大贡献。完成下面小题。
用所给词的适当形式填空
（1）The boy decided____(be)an actor at the age of 10.
②What’s the name of the tall____(build)?
③Darwin was a____(success)scientist of England.
④ At 25, Lily____(marry)a handsome man.
⑤The girl can speak several____(language).
Rt△ABC中，∠C=90°，CD⊥AB于点D，sin∠DCB=13,则sin∠A= ( )
