How Does Cell Phone Usage in the United States Compare

question 3

Multiple Choice

How does cell phone usage in the United States compare to Africa?

• A)There are more landlines in Africa because of limited resources.
• B)There are more cell phones in the United States because of higher incomes.
• C)In Africa there are few landlines;most people use cell phones.
• D)Cell phone usage is growing faster in the United States.

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Definitions:

Crinoids

Marine animals belonging to the class Crinoidea, characterized by a mouth on the top surface surrounded by feeding arms, part of the echinoderm phylum.

Trilobites

Extinct marine arthropods with a segmented body and calcified exoskeleton, prevalent from the Cambrian to the Permian period.

Cambrian Explosion

The widespread, relatively rapid appearance of diverse types of hard-shelled organisms near the beginning of the Cambrian Period.

Sedimentary Layer

A layer of sediment, typically deposited by water, wind, or ice, that has solidified into rock over geological time.