$(1$ point$)$ A manufacturing company incurs the fixed cost of $$5000.$ The variable cost is

$$7\mathrm{.}25$ per unit produced.

$($a$)$ Express the total cost as a function of the number $n$ of units produced.

Total cost is $($do not include the dollar sign$)$

$($b$)$ If the total cost is $$15875,$ how many units were produced?

units