How many minutes does it take devon to travel 10 miles at 40 miles per hour?

It would be 15 minutes. 

10/40 is 1/4, and 1/4 of an hour would be 15 minutes. 

There ya go :) 

In all honesty, there really is no “work” per say to show. mainly it’s just using the process of elimination. the question is asking which domain(s) would be the most appropriate for the function c(n). n is the number of observed vehicles so right away, 1, 2, and 3 can be eliminated.why? 1, 2 start in the negatives and therefore it is impossible to observe negative cars. so, #4 would be the best answer to the given problem.