please answer

Crazy Joe operates a canoe rental service on the Gualala River. He currently leases 15 canoes from a dealer in a nearby city at a cost of $10 per day per canoe. On weekends, when the water is high, he picks up the canoes and drives to a launching point on the river, where he rents canoes to white-water enthusiasts for $30 per day. Lately, canoeists have complained about the unavailability of canoes, so Crazy Joe has recorded the demand for canoes and found the experience below for the past 20 days: Recommend an appropriate number of canoes to lease