1 Find fy, fiy. o and f,, for the following function. (Remember, f,, means to differentiate with respect to y and then with respect to x.) f(x, y) =8x + 5y Findf,,, fxy' fvx' and fw for the following function. (Remember, fyx means to differentiate with respect to y and then with respect to x.) f(x, y) = 9yInx Find the relative maximum and minimum values. 2.2 fx,y)=x"+y +2x-4dy Select the correct choice below and, if necessary, fill in the answer boxes to complete your choice. O A. The function has a relative maximum value of fix,y) = at(xy)= (Simplify your answers. Type exact answers. Type an ordered pair in the second answer box.) () B. The function has no relative maximum value. Select the correct choice below and, if necessary, fill in the answer boxes to complete your choice. (O A, The function has a relative minimum value of f(x.y)= at (x,y) = ; (Simplify your answers. Type exact answers. Type an ordered pair in the second answer box.) () B. The function has no relative minimum value