Cepheid variable of great absolute brightness would probably exhibit______.
A. a relatively rapid variation in brightness
B. a correspondingly weak gravitational force
C. slow and almost invisible changes in brightness
D. a strong outward flow of light pressure
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In a world where information is a flood—______to everyone, and where nothing is secret or
A. acceptable
B. available
C. accessible
D. attainable
The writer holds that______.
A. modern technology has disturbed the quiet life of the people
B. modern technology has made people indifferent to noise pollution
C. modern technology has made the present world quieter than before
D. modern technology has failed to solve the problem of noise pollution
In paragraph 5 the word "buffs" means______.
A. settlers
B. enthusiasts
C. buyers
D. manufacturers
The passage implies that Leavitt's work on Cepheid variables would not have been possible
A. the camera as a scientific tool
B. techniques for determining the distances between stars
C. a method of measuring a star's gravitational force
D. an understanding of the chemical properties of stars
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