Consider the vector field "f = (12x, 0, -12x)", and let S be the triangle with vertices: (1, 0, 0), (0, 1, 0), (0, 0, 1). Determine the upward direction (hint: first find the equation of the plane containing S).
a) Along the positive x-axis
b) Along the positive y-axis
c) Along the positive z-axis
d) Along the normal to the plane containing S