1. 14.3, Partial Derivatives: (a) First Derivatives: The plane y = 2 intersects the graph of z = f(x, y) = xy3 + 5x2 in a curve, C. i. Calculate of at (x, y) = (3, 2). ii. Find a parametrization of the tangent line to the curve C at the point where x = 3. (b) Mixed Partials: In this multiple choice problem provide a justification for your answer. In the contour plot below dark shades represent small values of the function and light shades represent large values of the function. What is the sign of the mixed partial derivative? 2.OF 1.0 0.5 0.0 A 0.0 0.5 1.0 1.5 (a) fry > 0 ( b ) fay