The Astronomical Event That Is Now Thought to Have Occurred

question 98

Multiple Choice

The astronomical event that is now thought to have occurred some 65 million years ago,resulting in the death of a large fraction of all living species and leaving a layer of clay containing an enhanced concentration of a rare metal,iridium,in the geological record in rocks throughout the EarthEarth was a(n) :

• A) extraordinary solar eruption or flare.
• B) very large volcanic eruption on the EarthEarth.
• C) supernova that exploded relatively close to the solar system.
• D) asteroid impact on Earth.

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Definitions:

National Debt

The total amount of money that a country's government has borrowed, usually as a result of spending more than it receives in income.

Trillion

A numerical value representing a thousand billion, or 1,000,000,000,000, commonly used in discussing government budgets, economic indicators, and astronomical distances.

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The amount of federal securities outstanding, which represents what the federal government owes (the accumulation of federal deficits minus surpluses over the last two centuries).

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Gross Domestic Product, which is the total monetary or market value of all the finished goods and services produced within a country's borders in a specific time period.