Dart Board Probability

[mistykz]

Suppose you throw a dart at a circular target of radius 10 inches. Assuming that you hit the target and that the coordinates of the outcomes are chosen at random, find the probability that the dart falls:
a) within 2 inches of the center
b) within 2 inches of the rim
c) within the first quadrant of the target
d) within the first quadrant AND within 2 inches of the rim

I think I got part a. I just took the total area of the 10 inch board and subtracted the area of the 2 inch radius circle that we are aiming for. Is this correct?
I'm not sure on part b...my first guess was to take the area of the 10 inch dart board and subtract the area of a radius=8 circle, but this seems a bit too easy
For c, I believe the probability is 1/4, or 0.25
I can't figure out d as I do not have b

any help would be great! Thanks!

[Plato]

Suppose you throw a dart at a circular target of radius 10 inches. Assuming that you hit the target and that the coordinates of the outcomes are chosen at random, find the probability that the dart falls:
b) within 2 inches of the rim
d) within the first quadrant AND within 2 inches of the rim

For b) subtract the area of a circle of radius 8 from the total. Find the ratio.

For d) find one-fourth of that.