The author gives many examples to criticize Americans for their______.
A. cultural self-centeredness
B. casual manners
C. indifference towards foreign visitors
D. arrogance toward other cultures
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
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
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