Transportation service is considering improving the shuttle service capacity during morning hours from city T to city M. The analyst predicts the demand for this service during morning hours is 500 persons per hour. And the average transportation time is 23 minutes (including the time for the shuttles to go to M and return to T). Each shuttle has 35 seats. How many shuttles are needed for this service?
Round the answer to the nearest whole number. For example, if your answer is 2543.65, round to 2544; if you answer is 2543.12, round to 2543.