4. Let F(x, y, z) = [x cos(x2 + y?) + 1]i + lycos(x2 + y?) + zey=]j + (yeyz + 1)k. (a) Evaluate curl F. [5 marks] (b) Let G(x, y, z) = F(x, y, z) + zi. Is G a conservative vector field? Why? [5 marks] (c) Let I be the curve parametrizationindi+ , sinoj + cosok, o e [0, 2x]. Evaluate & G . dr with the G defined in question (c) above. [10 marks]