6 Two circles have circumferences of 10 cm
and 12 cm. What is the difference in their
radii?
7 A chord of a circle subtends an angle of 60°
at the centre of a circle of radius 7 cm. Find
the perimeter of the minor segment of the
circle.
8 A piece of thread was wound tightly round a
cylinder for 20 complete turns. The thread
was found to be 3.96 m long. Calculate the
diameter of the cylinder in cm.
9 Calculate the perimeter of a sector of a circle
of radius 27 cm, the angle of the sector being
140°.