Which information is not sufficient to prove that a parallelogram is the square

Isee the amount was $90.00 then reduced to $75.00 , what is the percent ?

What statement is true? 2x^2-9x+2=-1

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}