Where K is a constant to be determined. If it took Ian 45 minutes to exit the stadium when there were 5,000 people who drove and 1,500 people who took public transportation, how much time will it take Ian to exit if there are 12,500 people who drove and 4,00 who took public transportation? Round your answer to the nearest minute.

a. 90 minutes
b. 150 minutes
c. 42 minutes