[填空题]
On the diagram below, pn *n) qu5k6zztyf x 0)x)esm-roints X and t6qu,ahs:be ddjn 0+4Y are the centres of two circles containing the two arcna6 jt b,d4+s:uhdeq 0s from A to B.
1.Find the length from point A to point Y. mm
2.Find the perimeter of the shaded region. mm
3.Find the area of the shaded region. $mm^2$