solution with explanation please

Deming & Sons manufactures four grades of lubricant, W-10, W-20, W-30, and W-40, from a joint process. Additional information follows: If Processed Further Product W-10 W-20 W-30 W-40 Units Produced 67,200 48,000 38,400 38,400 192,000 Sales Value at Split-Off $ 400,000 344,000 232,000 176,000 $1,152,000 Additional Costs Sales Values $ 43,200 $ 438,000 34,400 400,000 23,200 288,000 14.400 192,000 $115, 200 $1,318,000 Required: Which, if any, of the four products would you recommend Deming & Sons sell at split-off (and not process further)? O:W-10 O W-20 OW-30 OW-40 O None of the products