Solve all please.

$($f$)$ What is the approximate $\backslash (0\mathrm{.}2\backslash \%\backslash )$ offset yield strength for the iron? Indicate how you determined this on your plot. $(1$ point$)$

$($g$)$ What is the ultimate tensile strength for the iron? $(1$ point$)$

$($h$)$ What is the engineering strain to failure for the iron? $(1$ point$)$

$($i$)$ Explain why a maximum in stress occurs in the engineering stress$-$strain curve for a polycrystalline metal deformed in tension. Why is there no maximum for the true stress$-$strain curve? $(1$ point$)$