Perform the indicated operations. Give a fully simplified answer.
a) (y+3)/(y²-16) ÷ (y²-y-12)/(y²+4y)
a) a) (y+3)/(y²-16) ÷ (y²-y-12)/(y²+4y)
b) (y+3)/(y²-16) + (y²-y-12)/(y²+4y)
c) (y+3)/(y+4) + (y-4)/(y+4)
d) (2y-1)/(y+4)