Change in Sales Mix and Contribution Margin that 18,700 additional Sun Sound and 20,400 additional Ear Bling headphones could be sold. The income from operations by unit of product is as follows: sufficient capacity for the additional production. Round your per unit answers to two decimal place. Change in Sales Mix and Contribution Margin that 18,700 additional Sun Sound and 20,400 additional Ear Bling headphones could be sold. The income from operations by unit of product is as follows: sufficient capacity for the additional production. Round your per unit answers to two decimal place