Phone Company

A new phone company has a network that can route 2000 calls between each of the following pairs of cities: (SF, LA), (SF, Bos), (SF, Chi.) (SF, Dallas), (LA, Chi.) , (LA, Dallas), (Chi. Dallas) , (Chi, Bos), (Chi., NY), (Dal., NY), (NY, Bos). The company has customers who have the following demands for calls per hour:
Cities Demand
SF - NY 1000
SF - Boston 3000
LA - Chicago 4000
Dallas - Boston 2000
Give a set of routes that allow all the calls to occur simultaneously.