The amount of time required to pick up liter in a park varies inversely with the...

...number of people working.....? The amount of time required to pick up liter in a park varies inversely with the number of people working. If five people take 4 hours to pick up liter, how many hours with three people take to pick up the liter?

A. 2.4hrs
B. 6 hrs
C. 7.5 hrs
D. 6.67 hrs
E. 5 hrs