Why Are Search Strategies for Extraterrestrial Life Usually Based on a Carbon

question 2

Multiple Choice

Why are search strategies for extraterrestrial life usually based on a carbon chemistry?

• A) Carbon dioxide is the main ingredient of planetary atmospheres,both terrestrial and Jovian.
• B) Carbon is abundant and is versatile in forming complex,long-chain molecules.
• C) Most meteorites that reach Earth are composed of carbon.
• D) No other atom can combine easily with the abundant hydrogen and helium to form long molecules in interstellar gas.

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Definitions:

Equity

The value of an ownership interest in property, including shareholders' ownership in a company.

Accounting Equation

The fundamental principle of accounting stating that Assets = Liabilities + Equity.

Measurement Principle

A financial accounting principle that determines the specific basis (historical cost or fair value) on which assets and liabilities are recorded in the financial statements.

Actual Cost

The incurred cost that reflects the real financial expenditure on a project, purchase, or activity.