A circle with centre O has radius 15cm. Two parallel chords AB and CD lie on opposite sides of O and the perpendicular distance between the chords is 14cm. If AB=24cm, answer the following.
(i) Find the perpendicular distance of each chord from the centre.
(ii) Calculate the length of CD.
(iii) Prove that the perpendicular bisectors of AB and CD intersect at O.