Find the increment and differential of each of the following functions for the given values of the variables and their increments. 15. xIn y + y In x; x = y = 1, Ax = 0.01, Ay = 0.02 16. y tan- xy; x = 2, y = 0.5, Ax = -0.05, Ay = 0.01 17. Find, approximately, the amount of metal in a closed tin can 3 inches in diameter and 5 inches high, if the metal is 1/32 inches thick.