19. The vectors x and y are shown below. Draw a diagram, including the resultant, to show the vector calculation 3* - 2 (3 marks) 20. Two forces of 20N and 40N act an angle of 40 to each other. Determine the resultant vectors of these two forces. (6 marks) 21. Given the points A(1,2,4), B(2,0,3), and C(4,4,4). Determine the Cartesian equation of the plane that contains these three points. (4 marks)