Ron is in charge of laying out the new rail line. As he supervised installation of rails he forgot to leave gaps to permit for heat expansion. Assume that, actually hot weather, rails increase in length by 1/20 inch for every 23 feet. If this were to cause the buckling of 1 mile of straight track into the isosceles triangle (with track raised up into air at half-mile mark) then how high off ground would track be lifted at midpoint?