As Sales Manager for Montevideo Productions, Inc., you are planning to review the prices you charge clients for television advertisement development. You currently charge each client an hourly development fee of $2,500. With this pricing structure, the demand, measured by the number of contracts Montevideo signs per month, is 15 contracts. This is down 5 contracts from the figure last year, when your company charged only $2,000.

1. Construct a linear demand equation in the form q = ap + b where the number of contracts q is given as a function of the hourly fee p Montevideo charges for development.
2. Give a formula for the total revenue obtained by charging $p per hour.
3. The cost to Montevideo Productions are estimated as follows:
Fixed cost: $120,000 per month and variable cost: $80,000 per contract.
Express Montevideo productions' monthly cost as a function of the hourly production charge p.
4. Express Montevideo Productions' monthly profit as function of the hourly production fee p.