The following figures have been extracted from Katy Perry's books of account for the month of April 2010:

Sales 460 000

Total variable costs 299 000

Total fixed costs 90 000 389 000

Profit 71 000

(a) Calculate Katy Perry's contribution as a percentage of sales (c/s ratio or contribution margin ratio).

(b) Calculate Katy Perry's break-even point in sales value (dollars).

(c) Calculate the sales in dollars necessary to make a profit of $100 000.

(d) Calculate the profit or loss if sales for the month are $375 000.

(e) If the original sales prices are reduced by 5% but costs do not change, calculate the value of sales needed to achieve a profit of $80 000