A hot upset-forging operation is performed in an open die. Initial diameter of the cylindrical work part D0 = 30 mm, and its height h0 = 50 mm. The part is upset to an average diameter of Df = 45 mm. The work metal at this elevated temperature yields at sy = 90 MPa. Coefficient of friction at the die-work interface is μ = 0.40. Determine (a) the final height of the part and (b) the maximum force in the operation. Show all your work and provide a narrative of the steps you take.