8 cm6cm 8cm0Fig. 12.5Fig. 12.6Fig. 12:6 shows two concentric circles withcentre O and radius 7 and R respectively.If R =3r, express the area of the shadedpart in terms of 77 and r.

8 cm6cm 8cm0Fig 125Fig 126Fig 126 shows two concentric circles withcentre O and radius 7 and R respectivelyIf R 3r express the area of the shadedpart in terms o class=