A stall owner at the art festival pays a salesman $60 per day to sell hand-painted silk scarves for $25 each. The owner also pays the salesman $0.75 per scarf sold. a) Determine a function that describes the income the sales makes for each day at the art festival. Define the variables in your function.

b) Determine a function that describes the profit the salesman generates each day for the stall owner. Define the variables of your function.

c) Determine the number of silk scarves the salesman must sell before the stall owner makes a profit from the sales.