The Mass of the Part of a Metal Rod That $S=4 x^{2}$

question 145

Multiple Choice

The mass of the part of a metal rod that lies between its left end and a point x meters to the right is $S=4 x^{2}$ . Find the linear density when x is 3 m.

• A) 4
• B) 20
• C) 24
• D) 12
• E) 18

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Definitions:

Invisible Hand

A concept proposed by Adam Smith, describing the self-regulating nature of the marketplace that guides individuals to unintentionally promote societal benefits through their own self-interest.

Self-Interest

Acting in a way that is most personally beneficial, often guiding economic decisions and behaviors.

Social Interest

The welfare or well-being of the general public and society as a whole, often considered in economic and policy decisions.

Consumer Sovereignty

The idea that consumers' preferences and choices dictate the types and quantities of goods and services produced by an economy.