Questions $9$ and $10$ refer to the following:

Jones Co$.$ had the following data for machine hours and maintenance costs in each of the four quarters of their prior fiscal year:

QUARTER $1$: $26$ hours and $$195$

QUARTER $2$: $24$ hours and $$193$

QUARTER $3$: $29$ hours and $$221$

QUARTER $4$: $37$ hours and $$255$

$9.$ What is the slope of the mixed cost equation for maintenance costs, using the Linear Regression method?

a$.$ $$10\mathrm{.}00$

b$.$ $$5\mathrm{.}00$

c$.$ $$14\mathrm{.}00$

d$.$ $$7\mathrm{.}00$

$10.$ Using the Linear Regression method and your answer from #$9$ above, what would be the cost estimated for the first quarter $of$ next year, $if$ the number $of$ machine hours for that quarter are estimated $tobe35?$

$b.$ $$221c.$ $$246$

b$.$ $$221$

d$.$ $$234$