4. In the figure, AQB is the minor arc of a circle with centre O and radius 34 cm. ARB is a semicircle with AB as its diameter and P as its centre. AOAB is a right-angled triangle with LOPB = 90° and LAOB = 68°. A R 2 P B 34 cm Find (i) the length of PB, (ii) the perimeter of the shaded region.