Answer:
See the three attached images.
Explanation:
image1 shows the intersection of b and c: 
 . (green "football")
. (green "football")
image2 shows the complement of a (outside a): 
 (yellow)
 (yellow)
image3 shows the intersection of those sets: 
 (green "football with a bite out of it") :-)
 (green "football with a bite out of it") :-)