Heidi receives utility from two goods, goat's milk (m) and strudel (s), according to the utility function

For utility U(m,s) = m*s, a. Show that os/8pm = 0, i.e. the price of one good doesn't affect this person's consumption of the other good. (This implies that om/op, = 0 too.) b. Use the Slutsky equation and the symmetry of net substitution effects to show that the income effects that involve your derivatives in part (a) are identical. c. Prove your result from part (b) explicitly, using the Marshallian demand functions for m and s