A flat, square surface with sides of length L is described by the equations (a) Draw this

Question:

A flat, square surface with sides of length L is described by the equations

(a) Draw this square and show the x-, y-, and z-axes.
(b) Find the electric flux through the square due to a positive point charge q located at the origin (x = 0, y = 0, z = 0). (Hint: Think of the square as part of a cube centered on the origin.)