Gmat prep, Circle area

[LFalken]

Could someone help me with this problem? It is supposed to have a figure with it, but all the figure is, is the shape of a ring.

the top side of a circular medallion made of a circular piece of colored glass is surrounded by a metal frame. If the radius of the medallion is r centimeters and the width of the metal frame is s centimeters, then in terms of s and r, what is the area of the metal frame, in square centimeters?

a) pi(r-s)^2
b) pi(r^2-s^2)
c) 2pi(r-s)
d) pi(r)(2r-s)
e) pi(s)(2r-s)

Thanks very much for anyone who has the time for this one. [/img]

[LFalken]

p.s. the answer is E.... Thanks!

[gauravgundal]

IMO E

The radius of circular medallion =r --- given
The width of metal frame =s --- given
The radius of the circular piece of colored glass=r-s

Area of the metal frame = Area of circular medallion - Area of circular piece of colored glass

= pi(r)^2 - (pi(r-s)^2)

= pi*s(2r-s)

[LFalken]

thank you!