The Total Numbers of Navy Personnel N (In Thousands) and Marines

question 183

Multiple Choice

The total numbers of Navy personnel N (in thousands) and Marines personnel M (in thousands) from 2000 through 2007 can be approximated by the models
$N ( t ) = 0.193 t ^ { 3 } - 3.88 t ^ { 2 } + 15.9 t + 370$ and $M ( t ) = 0.033 t ^ { 3 } - 0.21 t ^ { 2 } + 1.7 t + 171$
Where t represents the year, with t = 0 corresponding to 2000.

Find and interpret $( N + M ) ( t )$ .

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Definitions:

Nature

The physical world collectively, including plants, animals, landscapes, and other features and products of the earth as opposed to humans or human creations.

Land Rent

Payment made for the use of land, typically based on its productivity, location, and the competitive demand for land use.

Acres

A unit of measurement used primarily in the U.S. to describe the size of land, equating to 43,560 square feet.

Economic Rents

Extra earnings or return above the normal expected return of an investment or economic activity.