21. The Louisville and Nashville (L&N) Railroad had 10,400 mi of steel tracks throughout the southeast US when it was bought by the company that would become CSX in the 1980's. Suppose this length is measured at STP (32 F, 1 atm). During the summer, a blistering heat wave swept through, raising temperatures to 105 F. Assuming the temperature is the same for the whole region and the coefficient of linear expansion for steel is 6.5 x 10/F, what was the total length of the L&N line in the heat wave?