Hi Phi Sound Unlimited has a monopoly over the installation of surround sound systems. If Hi Phi Unlimited's total revenue from installing 15 sound systems is $30,000 and its total revenue from installing 18 sound systems is $33,000, what is the marginal revenue of the eighteenth sound system?

A) -$3,000
B) $1,000
C) $1,500
D) $3,000

Marginal Revenue

The boost in income generated from selling an extra unit of product.

Surround Sound Systems

Audio systems designed to create a more immersive listening experience by using multiple speakers placed around the listener to replicate a multi-dimensional sound environment.

Monopoly

A market structure characterized by a single seller controlling all supply of a good or service, with no close substitutes.