Required information [The following information applies to the questions displayed below.) Phillips Company manufactures air-conditioning units for commercial buildings and has noticed considerable variation in shipping expenses from month to month as per the data below: Units Total Shipping Month Shipped Expense January 4 $2,360 February 4 $3,260 March $2,8001 April $1,314 May June July 3 $2,310 6 $3,240 $4,704 8. If the air conditioners have an average sales price of $7,900, variable direct manufacturing costs are $3,950 per unit, variable manufacturing costs (excluding overhead) are $1,580 per unit, and variable selling and administration costs (excluding shipping) are $320 per unit, what is the contribution margin per unit? Contribution margin per unit