2. Seervada Park has recently been set aside for a limited amount of sightseeing and backpack hiking. Cars are not allowed into the park, but there is a narrow, winding road system for trams. You can see the simple graph of the road system below. O is the entrance into the park, other letters designate the locations of ranger stations. The numbers give the distances of these winding roads in miles. Park management would like to install telephone lines under the roads to establish telephone communication among all the stations. Because of the installation expenses, telephone lines will be installed under just enough roads to provide some connection between every pair of stations. Could you determine which lines should be used to accomplish the goal by minimizing total expense? (20 Points) 11 5 6 B D 1 o 3 9 7