A passenger is planning a trip that involves three connecting trains that leave from Stations A, B, and C, respectively. The first train leaves Station A every hour, beginning at 6:30 a.m., and arrives at Station B 
hours later. The second train leaves Station B every hour, beginning at 7:30 a.m., and arrives at Station C 
hours later. The third train leaves Station C every 30 minutes, beginning at 9:00 a.m. What is the least total amount of time the passenger must spend waiting between trains if all trains keep to their schedules?