The modulus of hdpe is 1.1 gpa and the yield strength is ~ 34 mpa. a cylindrical sample made from this polymer with a radius of 0.9 cm and length of 9 cm is subjected to a force of 5 kn. assuming the deformation is purely elastic what is the length of the sample after the force is applied? b) the stress associated with 5 kn is maintained on the sample for 1000 hr, and the length changes to 9.4 cm. what is the approximate modulus at this point? c) if the stress is removed at this point, will the length recover and go back to 9.0 cm? explain