12. (6') Find parametric equations for the line tangent to the curve of intersection of the surfaces at the given point. Surfaces: x2+ 2y + 2z = 4 y = 1 Point: (1, 1, 1/2) 13. (6') Find all the second order partial derivatives of g(x, y) = xy + 2sin(y) + 5ycos(x). d' g = ax 2 ag = axdy 14. (6') Find equations for the tangent plane and normal line at point Po(e, 11, 1) on the surface vin(xz2) = 11