Exxon Mobil and Shell Are Two of the Relatively Few

question 140

Multiple Choice

Exxon Mobil and Shell are two of the relatively few sellers in the oil-refining industry. Due to the tremendous capital investment required to enter this industry, these companies are insulated significantly from the threat of new competitive entrants and thus have considerable control over price. This market situation is referred to as a(n)

• A) cartel.
• B) monopoly.
• C) natural monopoly.
• D) oligopoly.
• E) trust.

---

Definitions:

Resolution

The smallest distinguishable increment into which a quantity is divided.

Input impedance

The impedance presented by an electrical device or circuit at its input, affecting how it interacts with the signal sources connected to it.

Ladder Logic

A programming language used in programmable logic controllers (PLCs) that employs graphical elements resembling a ladder with rungs to represent control logic.

Communication Module

Allows the user to connect the PLC to high-speed local networks that may differ from the network communication provided with the PLC.