Foster Corporation Has a Joint Process,which Produces Three Products,A,B and C.Each

Foster Corporation has a joint process,which produces three products,A,B and C.Each product may be sold at split-off or processed further and then sold.Joint processing costs for a year are $40,000.Other relevant data are:
$\begin{array}{llll}&\text { Sales Value }&\text {Separable Processing }&\text {Sales Value }\\ \text {Product }&\text {at Split-Off}&\text {Costs after Split-Off }&\text { at Completion}\\A&\$ 15,500 & \$ 2,200 & \$ 17,700 \\B&18,000 & 8,000 & 23,000 \\C&24,000 & 11,500 & 37,500\end{array}$
Required:
A) Which products should be processed further? Why?
B) If the Foster Company maximizes profits, what is the operating income?