the nick lumber company is in the process of deciding whether to sell or process further rough sawn lumber. the joint cost of producing the rough sawn lumber is $10,500. the following data is available.

lumber A: number of boards 3,000 , selling price per board (at split off) $16 (after additional procesing) $20, incremental cost to process further $5,000

lumber B: number of boards 2,000 , selling price per board (at split off) $24 (after additional processing) $30, incremental cost to process further $6,500

lumber C: number of boards 1,000 , selling price per board (at split off) $28 (after additional processing) $32, incremental cost to process further $5,500.

A) what Is the incremental effect, increase (or decrease) on operating income of processing each type of lumber further?

B) which type of lumber should be processed further?