Required information [The following information applies to the questions displayed below.] Barnes Company reports the following for its product for its first year of operations. The company sells its product for $140 per unit. Compute contribution margin using variable costing assuming the company (a) produces and sells 3,000 units and (b) produces 3,600 units and sells 3,000 units. Required information [The following information applies to the questions displayed below.] Barnes Company reports the following for its product for its first year of operations. The company sells its product for $140 per unit. Compute contribution margin using variable costing assuming the company (a) produces and sells 3,000 units and (b) produces 3,600 units and sells 3,000 units