An invoice received included the following information: merchandise price, $$5,600$; terms $1/10,$ n$/$eom; FOB shipping point with prepaid freight of $$539.$ Assuming that a credit for merchandise returned of $$1,100$ is granted prior to payment and that the invoice is paid within the discount period, what amount of cash should be paid by the buyer?

a$.$ $$4,994$

b$.$ $$6,078$

c$.$ $$1,100$

d$.$ $$5,600$