A steel surveyor's tape is to be used to measure the length of a line. The tape has a rectangular cross
section of 1.25 mm by 5 mm and a length of 30 m when T1 = 20°C and the tension or pull on the tape
is 100 N. Determine the true length of the line if the tape shows the reading to be 139 m when used
with a pull of 175 N at T2 = 40°C. The ground on which it is placed is flat. αst = 17(10-6)/°C, Est =
200 GPa.