For each of the following vector fields F, decide whether it is conservative or not by computing curl F. Type in a potential function f (that is, Vf = F). Assume the potential function has a value of zero at the origin. If the vector field is not conservative, type N. A. F(z, y) = (12x + 6y)i + (6x + 12y)j f(I, y) = B. F(z, y) = 6yi + 7xj f(I, y) = C. F(z, y, z) = 6xi + 7yj + k f(I, y, z) = D. F(z, y) = (6 siny)i + (12y + 6x cosy)j f(I, y) = E. F(x, y, z) = 6x2i + 6y j + 623k f ( I, y, z) =