Match the following functions with the appropriate cross-section: (10pts) I) z = (y²-1) cos(x) II) z=(x²-1) sin(y) III) z=- z = sin(x) cos(y) a) Which of the above functions has the following cross-section to the x-axis? Why? b) Which of the above functions has the following cross-section to the y-axis? Why?