One worker can produce 7 units of output with a selling price of $2.60 each. Even though the firm competes in an imperfect market, business is so good that the manager hires a second worker who produces 6 units. To sell these six additional units the firm must lower the price to $2.40 each. Similarly, the boss hires a third worker who adds 5 units to total product, and these units are worth $2.20 each. But to sell these 5 units, the workers must take a 20-cent price cut on the 13 units produced by the first two workers, so the third worker's MRP is only $8.40. Calculate the total revenue for the firm with three workers.