St. Paul Lumber Company incurs a cost of $528 per hundred board feet in processing certain "rough-cut" lumber, which it sells for $686 per hundred board feet. An alternative is to produce a "finished cut" at a total processing cost of $610 per hundred board feet, which can be sold for $910 per hundred board feet. a. What is the amount of the differential revenue? $ per hundred board feet b. What is the amount of the differential cost? $ per hundred board feet c. What is the amount of the differential income for processing rough-cut lumber into finished cut? $ per hundred board feet