a$\mathrm{.}1.$ The times it takes $($in minutes$)$ to create sign$-$up members at a homeless shelter soup kitchen are shown below. Five samples $($representing volunteers$)$ of four observations are taken.

Sample $1$

Sample $2$

Sample $3$

Sample $4$

Sample $5$

$10\mathrm{.}2$

$10\mathrm{.}3$

$9\mathrm{.}7$

$9\mathrm{.}9$

$9\mathrm{.}8$

$9\mathrm{.}9$

$9\mathrm{.}8$

$9\mathrm{.}9$

$10\mathrm{.}3$

$10\mathrm{.}2$

$9\mathrm{.}8$

$9\mathrm{.}9$

$9\mathrm{.}9$

$10\mathrm{.}1$

$10\mathrm{.}3$

$10\mathrm{.}1$

$10\mathrm{.}4$

$10\mathrm{.}1$

$10\mathrm{.}5$

$9\mathrm{.}7$

b$\mathrm{.}2.$ Before shipping lawn mowers to dealers, an employee starts each mower and records data for mowers that don't start on the first try. Out of $100$ mowers, an average of four did not start.