Question $4.$

Refer Figure $1$ in the addendum below that shows a V$-$groove with an included angle of $\backslash (50^\{\backslash$circ$\}\backslash )$ and a depth of $60$ mm that is tested by means of a precision ball $45$ mm in diameter.

$4\mathrm{.}1$ Make a drawing in the ANSWER BOOK making use of set of gauge blocks, a straight edge, and a precision roller of $45$ mm diameter.

$4\mathrm{.}2$ Calculate the thickness of the gauge blocks used in QUESTION $4\mathrm{.}1.$

$4\mathrm{.}3$ Describe how the V$-$groove angle of $\backslash (50^\{\backslash$circ$\}\backslash )$ should be checked. Figure $1$