Pie charts A, B and C are drawn to compare, over a given period, the total value of the sales of certain items in each of three branches of a multiple store. The radii of the charts are 20 cm, 30 cm and 40 cm, respectively.

(a) If the total sales value represented by chart B is 4500, calculate the total sales value represented by each of charts A and C.

(b) The angle of the sector representing a particular item in chart A is 72. Calculate the sales value of this item.

(c) The sales value represented by a sector in chart C is 600. Calculate the angle of the sector.

(d) One item occupies one quarter of chart A, and the sales value for this item is one half of that for the same item on chart B. Calculate the angle of the sector for this item on chart B. (C Additional)