1.) A pilot plans to make a flight lasting 2 hours and 30 minutes. How far can he fly from his base at the rate of 600 mph and return over the same route at the rate of 400 mph?

2.) Nina leaves her house on her bicycle at 9:30 AM and averages 5 kilometers per hour. Her sister, Ching leaves at 10 AM, following the same path and averaging 8 kilometers per hour. How long will it take for Ching to catch up with Nina? ​