Stratford Company distributes a lightweight lawn chair that sells for $20 per unit. Variable expenses are 30% of sales, and fixed expenses total $420,000 annually. 6. Refer to the original data. Assume again that the company sold 42,000 units last year. The president feels that it would be unwise to change the selling price. Instead, she wants to increase the sales commission by $2 per unit. She thinks that this move, combined with some increase in advertising, would double annual unit sales. By how much could advertising be increased with profits remaining unchanged? Do not prepare an income statement; use the incremental analysis approach. Increase in advertisement cost