A uniform, thin, solid door has height $2\mathrm{.}05$ m$,$ width $0\mathrm{.}875$ m$,$ and mass $21\mathrm{.}0$ kg$.$

$($a$)$ Find its moment of inertia for rotation on its hinges.

kg $$ m$2$

$($b$)$ Is any piece of data unnecessary? Select all that apply.

The height of the door is unnecessary.The width of the door is unnecessary.The mass of the door is unnecessary.No; all of the data is necessary.