There Are Four Lighthouses on the Island of Sand

question 202

Multiple Choice

There are four lighthouses on the island of Sand. If this is the efficient quantity of lighthouses

• A) the marginal social benefit of the fourth lighthouse equals its marginal social cost.
• B) total social benefit is zero.
• C) marginal social benefit minus marginal social cost is a maximum.
• D) Both answers A and C are correct.

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Definitions:

Gears And Shafts

Mechanical components that transmit rotational force; gears change the speed, torque, and direction of movement, while shafts support rotating parts and transfer motion.

Idler Gear

An Idler Gear is a gear positioned between two other gears to transmit motion from one to the other, often used to change the direction of rotation or to adjust the spacing between driving and driven gears.

Direction Of Rotation

The clockwise or counterclockwise movement of a mechanical component or system as seen from a specific vantage point.

Drive Gear

Any gear that drives another.