Consider the vector field F(x, y, z) = (z³ + 2 x y − 1) î + x² ĵ + 3x z² k. i) Show that Ę is a conservative vector field. ii) Find the scalar potential function (x, y, z) associated with F. F. dr where P and Q are iii) Use the result of ii) to evaluate the line integral for the respective points (1, 2, 3) and (−1, −2, −3).