pls explain ad solve both

Consider the two variable function f(xy) = xIn( 79y +1) Find the value of the second-order differential of the function at the point where x = 2.8 and y = 0, given the change in variable x is dx = 8.2 and the change in variable y is dy - 13. AnswerSelect the correct statement or statements among those below. a. A concave function has concave level curves. b. A concave function can have convex level curves. c. A convex function can have concave level curves. d. A strictly concave function has strictly concave level curves. O e. None of the other statements is correct. f. A convex function has convex level curves. g. A strictly convex function has strictly convex level curves. h. A strictly concave function must have concave level curves but not necessarily strictly concave level curves