A triangle PQR is right-angled at Q and is drawn inside a circle so that all three vertices lie on the circumference. The lengths of the perpendicular sides are PQ=8cm and QR=15cm.
a. (i) Prove that PR is a diameter of the circle.
b. (ii) Determine the radius of the circle.
c. (iii) Calculate, correct to one decimal place, the area of the circle.