7

7. (8+6+6) (a) Find a non-zero vector that is perpendicular to the plane containing the points P(-2, 0, 4), Q(1, 3, -2) and R(0, 3, 5). (b) Find the area of the triangle PQR, P, Q and R are as in part (a). (c) Find the volume of the parallelepiped determined by the vectors a, b and c where a = (1, 2, 3), b = (-1, 1, 2) and c = (2, 1, 4)