Show solution, answers should be:

$1\mathrm{.}17$: a E $=20,000$ ksi, b $\backslash$sigma y ~ $70$ ksi, c $\backslash$sigma y ~ $68$ ksi, d Esecant ~ $17,200$ ksi, e Etangent ~ $5,400$ ksi

$1\mathrm{.}18$: I expect some variability on modulus values, a ur ~ $0\mathrm{.}063$ k$-$in$/$in$3,$ b ut ~ $0\mathrm{.}68$ k$-$in$/$in$3,$ c

u $=0\mathrm{.}285,$ d permanent strain ~ $0\mathrm{.}0018$