Work on this problem in the provided answer sheet and submit through Gradescope. Answer the following questions based on the given diagram. 600 500 400 500 Stress (MPa) 300 400 300 Stress (MPa) 200 200 100 100 0.000 0.006 0.002 0.004 Strain 0 0.00 0.04 0.08 Strain 0.12 0.16 0.20 A sample with a square cross section of 15 mm x 15 mm was initially 120 mm long. a. (O point) What is the given initial dimension (cross section area and length)? (don't forget the unit!) b. (2 points) What is the yield stress value? (don't forget the unit!) Also, how do you determine this? c. (4 points) If the sample is under 30 kN load, what is the stress value? Show your work. Include original equations and units in each step. d. (3 points) What is the final length of this material after a load of 30 KN is applied and released? Show your work. Include original equations and units in each step. Also, include an explanation that justifies your