points P, Q, and R are given.

a. Find the general equation of the plane passing through P, Q, and R.

b. Write the vector equation n PS = 0 of the plane at a., where S(x, y, z) is an arbitrary point of the plane.

c. Find parametric equations of the line passing through the origin that is perpendicular to the plane passing through P, Q, and R.

P(2, 1, 4), Q(3, 1, 3), and R(2, 1, 0)