Garber plumbers offers a 20% trade discount when providing $2000 or more of plumbing services to its customers. In march 2012, garber provided $4000 of plumbing services to red oak, inc. and $1500 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 sales figure for these two transactions? A. 5500 B. 4312 C. 4486 D. 4606.