Four points P(1,1), Q(1,6), R(7,6) and S(7,1) are the vertices of a figure.
a. (i) Plot P, Q, R and S on the Cartesian plane and join them in order.
b. (ii) Using the coordinates, find the lengths of the sides PQ and QR.
c. (iii) Calculate the perimeter of the figure.
d. (iv) Find the area enclosed by the figure.