The Isotope Has a Half-Life of 7

question 55

Multiple Choice

The isotope has a half-life of 7.5 seconds. If a sample contains 144 atoms of approximately how many such atoms were there present 30 seconds earlier?

• A)576
• B)1152
• C)2304
• D)4320
• E)4.30 × 10 ⁸

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Definitions:

Centrally Planned Economic System

An economic system in which the government or state makes all decisions about what to produce, how to produce, and for whom to produce, with little or no input from market forces.

Consumers

Individuals or groups who purchase goods and services for personal use and not for manufacture or resale.

Privately Owned Businesses

Companies that are owned by individuals or private groups, not controlled by the government.

Mixed Economies

A system combining elements of both capitalism and socialism, where both private enterprise and government play important roles in the economy.