Marianne is considering setting up a gourmet truffle shop. The estimated cost of making a gift box of truffles includes the gold box at $1.50 each and the truffles at $4.50. As well, weekly costs include rent of $230, electricity of $120 and wages of $320. Marianne plans to sell each box at $12.50. Marianne's fixed cost will be $ per week and her variable cost \$ per box. To break even she needs to sell boxes of truffles. In term of sales revenue, this is equal to If the rent increase to $260 per week, she needs to sell more boxes to break even