Material 1 costs $7 a pound, material 2 costs $5 a pound, and labor costs $15 per hour. Product A sells for $101 a unit, product B sells for $67 a unit, and product C sells for $97.50 a unit. Each week there are 300 pounds of material 1; 400 pounds of material 2; and 200 hours of labor. The output of product A should not be more than one-half of the total number of units produced. Moreover, there is a standing order of 10 units of product C each week. By how much would the profit contribution of product A has to increase before it will be profitable to produce A