If f(x, y) = 4 - x² - 3y² , find fₓ(1, 0) and fy(1, 0) and interpret these numbers as slopes. Illustrate with either hand-drawn sketches or computer plots.

a) fₓ(1, 0) = -2 , fy(1, 0) = 0
b) fₓ(1, 0) = 0 , fy(1, 0) = -3
c) fₓ(1, 0) = -2 , fy(1, 0) = -3
d) fₓ(1, 0) = 2 , fy(1, 0) = 3