Computer Conventions has presented Wei with three booth rental options. Her first option is to rent the booth for the fixed amount of $2,000. Her second option is to pay a fixed amount of $800 and an additional $30 charge (15% of her $200 selling price per unit) for every unit she sells. Her third option is to pay a $50 charge (25% of her $200 selling price per unit) for every unit she sells.