Which of the following factors in the simplified Drake equation is best known?
A) Nhp, the number of habitable planets in our galaxy
B) fciv, fraction of life-bearing planets where intelligent civilizations have arisen at any time
C) fnow, fraction of civilization-bearing planets that have intelligent civilizations on them now
D) flife, fraction of life-bearing habitable planets
A
Physics & Space Science
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Neptune has a single, broad ring that is extremely thin
Indicate whether the statement is true or false
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The meaning of the word "energy" is immediately clear to anyone
What will be an ideal response?
Physics & Space Science
Determine the equivalent capacitance of the combination shown when C = 15 mF
a.
20 mF
b.
16 mF
c.
12 mF
d.
24 mF
e.
75 mF
Physics & Space Science
An absorption spectrum is also called a bright-line spectrum
Indicate whether the statement is true or false
Physics & Space Science