The Great Chicago Bank soon will be hooking up computer terminals at each of its branch offices to the computer at its main office using special phone lines with telecommunication devices. The phone line from a branch office need not be connected directly to the main office. It can be connected indirectly by being onnected to another branch office that is connected (directly or indirectly) to the main office. The only requirement is that every branch office be connected by some route to the main office. The charge for the special phone line is $100 times the number of miles involved, where the distance (in miles) between every pair of offices is provided in the following table: Distance between Pairs of Offices Branch 1 Branch 2 Branch 3 Branch 4 Branch 5 Main office 190 70 115 270 160 Main office Branch 1 190 100 110 215 50 Branch 2 70 100 140 120 220 Branch 3 115 110 140 175 80 Branch 4 270 215 120 175 310 Branch 5 160 50 220 80 310 Management wants you to determine which pairs of offices should be directly connected by special phone lines in order to connect every branch office (directly or indirectly) to the main office at a minmum total cost