Suppose that a firm has made the following computations for its design for disassembly:

processing cost per unit $=$$$12\mathrm{.}00,$ disposal cost per unit $=$$$6\mathrm{.}00,$ resale revenue per unit $=$

$$20\mathrm{.}00,$ and recycling revenue per unit $=$$$7\mathrm{.}00.$ What is the revenue retrieval for this product?

a$.$ $$9\mathrm{.}00$

b$.$ $$20\mathrm{.}00$

c$.$ $$1\mathrm{.}00$

d$.$ $$8\mathrm{.}00$

e$.$ $$27\mathrm{.}00$