The management of Acrosonic plans to market the ElectroStat, an electrostatic speaker system. The marketing department has determined that the demand for these speakers is represented by the following function, where p denotes the speaker's unit price (in dollars) and x denotes the quantity demanded. Find the following functions (in dollars), find the value (in dollars) and interpret your results. p = −0.02x + 610 (0 ≤ x ≤ 20,000)

a. Find the revenue function R.
b. Find the marginal revenue function R'(x).
c. Compute the following value.
R'(5,400) =