R. A star’s brightness stays the same over any distance, so each of those stars would be visible to us,
and the heavens would be filled with light.
S. The fact that they are not indicates that there is something fundamentally wrong with the popular
conception of the universe.
T. In an infinite universe, after all, there would have to be a star lying in every possible line of sight in
the sky.
U. Halley’s question is in fact interesting to consider because if the universe were truly infinite, as most
suppose, the entire sky would be ablaze at night.
Paragraph 4
The philosophers in eighteenth-century France had a direct and strong influence upon the revolutionary movement of 1789.
Q. This may seem surprising, given that most French people experienced poverty and starvation.
R. This miserable situation would appear to have been enough by itself to inflame the masses.
S. However, until they were provided with the idea of revolution, the people expressed their
dissatisfaction only in occasional riots.
T. In fact, it is safe to say that there would have been no revolution at all without their writings and
lectures.
U. They provided a dramatic example of the cliché “The pen is mightier than the sword.”
4.
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The study of indoor environmental pollution is a controversial new area of scientific research.
Q. For example, inhabitants of houses with statistically “average” levels of radon are exposed to
approximately 300 percent more radiation than the average American receives from X-ray medical
procedures in a lifetime.
R. Consequently, it is a serious concern that hundreds of thousands of homes exceed “average”
pollution levels.
S. One area of debate is that the use of the terms “high,” “low,” and “average” in reports of the
concentrations of indoor pollutants can be misleading.
T. Clearly, more attention needs to be paid to issues such as the labeling of indoor pollutant
concentrations.
U. Such labels do not necessarily imply any correlation with “acceptable” or “unacceptable” health
risks.
5.
