Using the values you calculate for e, g, and ν determine what material was tested via a tabulated source (such as that in the appendix of your strength of materials textbook). using your judgment, select an appropriate yield stress and determine at what longitudinal strain your calculated value of poisson’s ratio is no longer valid. based on your physical observations from lab 1, would you expect poisson’s ratio to increase or decrease after this point? justify your answer. also, could a digital caliper with accuracy of ±0.0005in be used in place of the strain gages to measure the thickness of the cross-section? explain.