8.4 The following data were obtained in a tensile test on a specimen with 50 mm gauge length and a cross-sectional area of 160 mm. The total elongation of the

specimen just before final fracture was 16%, and the reduction in area at the fracture was 64%. Find the maximum allowable working stress if this is to equal a. 0.25 x tensile strength b. 0.6 x 0.1% proof stress