Solve the problem. (Chain Rule) (6 Points Each) 14) Evaluate W dt at t = on for the function w(x, y) = x2 - y2 + 8x; x = cost, y = sint. 15) Evaluate - dw dt att = _it for the function w(x, y, z) =-2; x = sint, y = cost, z= +2. 16) Evaluate - at t = 9 for the function w(x, y) = ey - In x; x = ?, y = Int.Find the limit. (6 Points Each) 9x2 + 9y2 + 8 3) lim (x, y) - (0, 0) 9x2 - 92+4 4) lim (x, y) - (3,5) V xy Find the limit. lim 5) p - (6, 6, 8) sec2 x - tan2 y + z