Determine whether or not each of the following relations is a function. If a relation is a function, find its range.
(a) {(x, y)\x, y ∈ Z, y = x2 + 7}, a relation from Z to Z
(b) {(x, y)|x, y ∈ R, y2 = x}, a relation from R to R
(c) {(x, y)\x, y ∈ R, y = 3x + 1}, a relation from R to R
(d) {(x, y)\x, y ∈ Q, x2 + y2 = 1}, a relation from Q to Q
(e) R is arelation from A to B where | A| = 5, |B| = 6, and |R| = 6.