A steel tape 20 meter long standardise at 15°c with pull of 10kg. watch use to measure distance along a slope of 4°25'. If the mean temperature during measurement was 10°c and the pull applied 16kg, determine the correction required per tape length. Assume co-efficient of linier expansion=112×10^-7 and area=0.8cm^2 and Youngs modulus(E)= 2.1×10^6 kg/ cm^2.