4 (a) A, B, C, D and E are five points on the circumference of a circle. EB is parallel to DC, EACˆ = 72° and AEBˆ = 25° . X is the intersection of AC and EB. Find (i) EBCˆ , (ii) CXBˆ , (iii) EDC ˆ, (iv) ACDˆ . (b) The angle of a sector of a circle, radius 6 cm, is 40°. (i) The area of the sector is kπ cm2. Find the value of k. (ii) Find an expression, in terms of π, for the perimeter of the sector. Give your answer in the form (a + bπ) centimetres. (iii) A geometrically similar sector has perimeter (72 + nπ) centimetres. Find the value of n.