Wade company is operating at 75% of its manufacturing capacity of 140,000 product units per year. a customer has offered to buy an additional 20,000 units at $32 each and sell them outside the country so as not to compete with wade. the following data are available: costs at 750% capacity: per unit $12.00 $1.260,000 total direct materials direct labor 945.000 9.00 1.575,000 $36,00 $3.780,000 overhead (fixed and variable) totals 15.00 in producing 20,000 additional units, fixed overhead costs would remain at their current level but incremental variable overhead costs of $6 per unit would be incurred. what is the effect on income if wade accepts this order? income will decrease by $4 per unit. income will increase by $4 per unit. income will increase by $5 per unit. income will decrease by $5 per unit. income will increase by $11 per unit.