24. Multiple Choice: Circle the best answer.
 The commercial jet that travels from Chicago to New York averages about 400 mi/h. The air distance from
 Chicago to New York is 713 miles. Write a function to represent the distance d remaining on the tript
 hours after takeoff.
 a. d = 400 - 713t
 b. d = 713 - 4000
 C. d = 400t + 713
 d. d = 713t+ 400