Would like a step by step method on how to solve, please and thanks :))

Bricks sells its side tables (as pair) for $300. Last week, Bricks sold 10 side tables in a seasonal sales campaign. This campaign incurred a weekly variable costs comprised of $85 for overhead and $105 total COGS (not pair). Bricks also had a fixed cost of $1,500. Please calculate their unit variable cost for the pair