Garber Plumbers offers a 20% trade discount when providing $2,000 or more of plumbing services to its customers. In March 2018, Garber provided $4,000 of plumbing services to Red Oak Inc., and $1,500 of services to Cyril Inc., Each of these customers was granted credit terms of 2/10, net 30. If both customers paid for the plumbing services within the discount period, what was the net revenues amount for these two transactions?

a. 5,500

b. 4.312

c. 4,486

d. 4,606