A material must be selected for a spring.

$($a$)$ What quantity must be maximized to select the best material for the spring? $(0\mathrm{.}5$ point$)$

$($b$)$ What is the material index for the spring? $(0\mathrm{.}5$ point$)$

$($c$)$ Use the Ansys GRANTA EduPack software $($with the Level $2$ database$)$ to make the appropriate property chart and select the best four metals $($or alloys$)$ for springs. $($you must submit a copy of the property chart with your selection line indicated$).$ Note: it is preferred to limit the materials for the plot to metals and alloys, because this simplifies the identification of the best metals. $(1$ point$)$