Two rods, one of butadiene rubber (BR) and one of high-density polyethylene (HDPE), are rigidly connected in series. The BR rod is 1m long with a diameter of 10mm, while the corresponding dimensions for the HDPE rod are 0.8m and 5mm, respectively. Let the tensile modulus for BR be 1.6Mpa and the corresponding value for HDPE= 0.7Gpa. Determine the final length of the rod when a weight of 3kg is applied in tension.