According to the passage, the absolute brightness of a Cepheid variable______.
A. depends upon its measurable distance from an observer on earth
B. may be determined from the length of its cycle of variation
C. changes from time to time according to a regular and predictable pattern
D. indicates the strength of the gravitation force exerted by the star
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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
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
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