At cycle and sport, customers can rent bikes, electric scooters, kayak, canoes, or paddleboards by the hour. kenny rents a bike and a helmet. the expression 9b + 6 represents the total cost to rent the bike for 6 hours, plus the feet for the helmet

what does the term 9b represent?
1. the cost to rent a bike
2. the number of hours
3. the total cost, including the helmet rental
4. the cost to rent a helmet