shiro is the only provider of luxurious sushi in town. To enjoy Shiro's sushi, the customers have to pay a fixed fee f to become the member, and pay p for each unit of sushi. Suppose the inverse demand function of Shiro's sushi is p(q)=12.5-3.6q, which is known to Shiro, and the marginal cost of sushi is MC=4.7. To maximize the profits, Shiro determines the optimal level of f and p. How much is the resulting profit? Round your answer to 2 decimal points.