Question 6 (a) Show that the vector field F(x, y, z ) = 2czer +xi+ 2yzer +y jtextx k is a conservative vector field. (6 marks) (b) Hence, or otherwise, compute the line integral F.dr c where C is the closed path r(t) =3cos(f) i + 3sin(t)j + sin(t) k, for 0