A 1-cm-thick copper plate is cold-reduced to 0.50 cm and later further reduced to 0.16 cm. determine the total percent cold work and the tensile strength of the 0.16 cm plate.
a) 36% cold work, tensile strength of 270 MPa
b) 42% cold work, tensile strength of 310 MPa
c) 28% cold work, tensile strength of 240 MPa
d) 48% cold work, tensile strength of 330 MPa