F.4 circle

1)
http://img97.imageshack.us/img97/8150/dsc00564jv.jpg
AC,AD and BE are tangents to the circle.
If AC=12cm,find the perimeter of triangle ABE.
ans: 24cm

2)
AB,AC and BC are three tangents to the circle at D,E and F respectively.If
AB=8cm ,BC=6cm and angle ABC=90,the area of the shaded region.
ans: 24-4 pie

pls show steps.thz!