a 20-mm rod made of an experimental plastic is subjected to a tensile force of magnitude P=6kN. Knowing that an elongation of 14 mm and a decrease in diameter of 0.85 mm are observed in a 150-mm length, determine the modulus of elasticity, the modulus of rigidity, and Poisson's Ration for the material. Also find the change in volume of the cylindrical rod, and the hydrostatic stress in the rod. Using the change in volume and the hydrostatic stress, calculate the bulk modulus of the material. And lastly, calculate the bulk modulus of the material using Young's Modulus and Poisson's Ratio.