Part a and b are right, but It says part C is wrong...

Profit from Processing Further Deaton Corporation manufactures products A, B, and C from a joint process. Joint costs are allocated on the basis of relative sales value of the products at the split-off point. Additional information for Deaton Corporation follows: Required: 2a. For each of the three products (A, B, and C), calculate the differential benefit (loss) from processing the product after the split-off point rather than selling the product at the split-off point. (Loss amounts should be indicated with a minus sign.)