Consider X and Y such that the joint density fX,Y (x,y) of X and Y is Uniform

Question:

Consider X and Y such that the joint density fX,Y (x,y) of X and Y is Uniform on the square where 0 ≤ X, Y ≤ 1. In other words,
fX,Y(x, y) = 1
if 0 ≤ x ≤ 1 and 0 ≤ y ≤ 1,
and fX,Y (x,y) = 0 otherwise.
a. Are X and Y dependent or independent?
b. Find the covariance Cov(X2, X + Y) of X2 and X + Y.
c. Find the correlation Cov(X2, X + Y) of X2 and X + Y