For Which of the Following Factors in the Drake Equation

question 95

Multiple Choice

For which of the following factors in the Drake equation do we actually have observational knowledge,rather than just a speculative estimate?

• A) R_*,the rate at which solar-type stars form in the Galaxy
• B) f_l,the fraction of Earthlike planets on which life actually arises
• C) f_i,the fraction of life forms that evolve into intelligent species
• D) f_c,the fraction of intelligent species that develop adequate technology and then choose to send messages out into space

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Definitions:

Consequent

In logic, this refers to the outcome in a conditional statement, which follows from its condition (if-then statement).

Proposition

A proposition is a statement or assertion that expresses a judgment or opinion.

Syllogism

A form of deductive reasoning that arrives at a conclusion based on two premises, where each shares a common term.

Premise

A statement or idea that is accepted as a truth and serves as the basis for an argument or reasoning.