Weber's Mail Manufacturing is a company that produces chain mail. Their most popular product is saw-cut metal links that hobbyists can use to make their own creations. The company recently spent $600 on advertising, which they hope to make back quickly. The wire used to produce one ounce of links costs $1, but the finished links sell for $4 per ounce. Eventually, the company will make back its investment and break even. What will their expenses and sales both equal?