How have astronomers measured the acceleration of the universe?
A) by measuring changes in galaxies' redshifts from year to year
B) by comparing lookback times for white-dwarf supernovae (by measuring their apparent brightness) with the average distance between galaxies (based on their cosmological redshifts)
C) They have not. It is a purely hypothetical idea.
B
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State the law of conservation of electric charge
What will be an ideal response?
The most striking example of solar variability was:
A) the Dust Bowl drought of the 1930s. B) the Maunder Minimum from 1645-1715. C) the Sporer Minimum that doomed the Anasazi. D) the fall of Rome. E) Joseph's seven lean years in the Old Testament.
What did Galileo incorporate in his study of motion that Aristotle overlooked?
A) the role of distance B) the role of time C) the role of space D) none of the above
_________are used to determine temperature based upon the electrical resistivity of a material.
Fill in the blank(s) with the appropriate word(s).