What Did Carl Sagan Mean When He Said That We

question 134

Multiple Choice

What did Carl Sagan mean when he said that we are all "star stuff"?

• A) that life would be impossible without energy from the Sun
• B) that the Earth formed at the same time as the Sun
• C) that the carbon, oxygen, and other elements essential to life were created by nucleosynthesis in stellar cores
• D) that the Sun formed from the interstellar medium: the "stuff" between the stars
• E) that the Universe contains billions of stars

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Definitions:

MTBF

Mean Time Between Failures; a reliability measure of the average time a product or system operates before failing.

Component Reliability

The probability that an individual part or component of a system performs its intended function under specified conditions for a designated period of time.

Preventive Maintenance

Regular and systematic inspection, cleaning, and replacement of worn parts, materials, and systems to prevent sudden failure and downtime.

Breakdown Maintenance

Maintenance work performed after a machine or system fails to restore it to operational condition.