A bed and breakfast charges $85 for a room per night. Market research shows that for each $10 raise in price one more room will be vacant. If the bed and breakfast has a total of 8 rooms, then. . .
a) Determine the demand function
b) Use part (a) to calculate what price and revenue is when 6 rooms are occupied.
c) Calculate when the marginal revenue is zero. Find what the revenue is at this time.