Write the coordinates of each of the following points and mention the quadrant or axis on which it lies:
(a) A point P that is 7 units right of the y-axis and 3 units below the x-axis.
(b) A point Q that is 221 units left of the y-axis and 6 units above the x-axis.
(c) A point R that lies 4 units above the x-axis and exactly on the y-axis.
(d) A point S that is 8 units below the x-axis and exactly on the y-axis.