If a company's fixed costs are $$180,000$ and their variable cost per unit is $$8\mathrm{.}60$ what is their cost per unit if they sell $50,000$ units?

A$.$ $$3\mathrm{.}60$ per unit

B$.$ $$12\mathrm{.}20$ per unit

C$.$ $$5\mathrm{.}00$ per unit

D$.$ $$8\mathrm{.}60$ per unit