Charlene and Gary want to make perfume. In order to get the right balance of ingredients for their tastes they bought 2 ounces of rose oil at $4.96 per ounce, 5 ounces of ginger essence for $4.24 per ounce, and 3 ounces of black currant essence for $2.04 per ounce. Determine the cost per ounce of the perfume.