Michelle, Jennifer, and Betty volunteered to make cupcakes for a school fundraiser. They've been asked to make 100 cupcakes. Michelle can make 6 cupcakes in an hour. Jennifer can make 18 cupcakes in two hours. Betty can make 24 cupcakes in two hours. How long will it take to make 100 cupcakes if they work together?

A. 3 19/27 Houurs
B. 2 2/9 Hours
C. 4 1/6 Hours
D. 1 23/27 Hours