A tensile test specimen having a gauge length of 50 mm was tested to fracture. The stress-strain diagram from this tension test is shown in the figure. At which axial stress (approximately) the specimen will observe a permanent elongation of 3mm after unloading? the Stress (MPa) 480 360 240 120 0.00 0.00 ABA Upper scale Lower scale B 0.04 0.08 0.12 0.16 0.20 0.002 0.004 0.006 0.008 0.010 Strain (mm/mm)