A politician raises funds by selling tickets to a dinner for $700. The politician pays $140 for each dinner and has fixed costs of $6,000 to rent a dining hall and wait staff. Write the profit P in dollars as a function of x, and the numbers of dinners sold. P(x)= . Show that the derivative of the profit function is a constant and is equal to the increase in profit from each diner sold. P’(x)= , which equals the