Which of the following cases in the Drake equation would be the minimum necessary condition for us to be the only intelligent civilization currently in our galaxy?
A) any two of the factors to be zero
B) any three of the factors to be zero
C) all of the factors to be zero
D) any one of the factors to be zero
D
You might also like to view...
The helium flash converts helium into ________
Fill in the blank(s) with correct word
Observations of type Ia supernovae reveal that the expansion of the universe is speeding up because of the presence of ___________ in empty space
Fill in the blank(s) with correct word
The Dirac theory predicted that a positron would be
a. a negative electron in a negative energy state. b. a particle with same mass as an electron but with opposite charge. c. a particle with negative mass. d. All of the above.
A pipe that is 0.46 m long and open at both ends vibrates in the second overtone with a frequency of 1150 Hz. In this situation, the distance from the center of the pipe to the nearest antinode is closest to
A) 7.7 cm. B) 3.8 cm. C) 12 cm. D) 15 cm. E) zero.