a nickel stell has engineeringnstress of 610 N/mm2 . The reduction in area of cross section at the fracture was 38 %. The true stress in the material is

• A. 0.442 kn/mm2
• B. 0.881 kn/mm2
• C. 1.605 kn/mm2
• D. 0.232 kn/mm2