Finding the area of each

If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=

Find the distance between the pair of points a(-1,8) and b(-8,4)

Let u = {q, r, s, t, u, v, w, x, y, z} a = {q, s, u, w, y} b = {q, s, y, z} c = {v, w, x, y, z}. list the elements in the set. a ∩ (b ∪ c)a) {q, s, w, y}b) {q, y, z}c) {q, s, u, w, y, z}d) {q, r, w, y, z}