Which Factor in the Modified Drake Equation Are We Best

question 50

Multiple Choice

Which factor in the modified Drake equation are we best able to estimate?

• A) N_hp, the number of habitable planets in our galaxy
• B) f_civ, fraction of life-bearing planets where intelligent civilizations have at some time arisen
• C) f_now, fraction of civilization-bearing planets that have intelligent civilizations on them now
• D) f_life, fraction of life-bearing habitable planets which are intelligent now

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Definitions:

Forced Expiration

The act of expelling air from the lungs with effort beyond normal exhalation.

Diaphragm

is the primary muscle used in the process of breathing, separating the thoracic cavity from the abdominal cavity.

External Intercostals

Muscles located between the ribs that help expand the chest cavity during inhalation.

Prime Mover

The muscle or group of muscles primarily responsible for generating a specific movement in the body.