Which is used observationally to determine the age of a star cluster?
A) the total number of main-sequence stars
B) the luminosity of the main-sequence turn-off point
C) the amount of dust that lies around the cluster
D) the number of white dwarfs
E) the ratio of giants to supergiants
B
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Many of the ancient astronomers applied astrology alongside astronomy, but that no longer holds true for modern astronomers. Explain why astrology is no longer considered useful to the modern scientist
What will be an ideal response?
What would happen if Jupiter was suddenly replaced by a black hole with the same mass as Jupiter?
A) The orbits of the planets in our solar system would be unaffected. B) The other planets would slowly be pulled into Jupiter, but the Sun would be unaffected. C) The other planets and the Sun would slowly be pulled into Jupiter. D) The entire solar system would rapidly be sucked into the black hole.
Dispersion results because the speed of light in a transparent medium varies with frequency
Indicate whether the statement is true or false
Discuss how web designers create forms that follow UX principles.
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