Evidence from the analysis of zircon crystals suggests that the Earth
A) may have been habitable immediately after its formation
B) could only have been habitable after significant amounts of oxygen had built up in its atmosphere
C) could only have been habitable after the end of the Hadean Eon 500 million years ago
D) may have been habitable in as little as 100 million years after its formation
D
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Self-interstitials are produced when metals are _____________ deformed.
Fill in the blank(s) with the appropriate word(s).
In our solar system, Jovian planets are
A) large, made mostly of gases and liquids with low densities, and found far from the Sun B) small, made of pure rock with high densities, and found close to the Sun C) large, made of pure gases with low densities, and found far from the Sun D) small, made mostly of rock and iron with high densities, and found close to the Sun
Which of the following statements about open clusters is true?
A) All stars in the cluster will evolve similarly. B) All stars in the cluster have approximately the same mass. C) All stars in the cluster are approximately the same color. D) There is an approximately equal number of all types of stars in the cluster. E) All stars in the cluster are approximately the same age.
What is the maximum number of 60-W light bulbs you can connect in parallel in a 100-V home circuit without tripping the 30-A circuit breaker?
a. 18 b. 24 c. 49 d. 36 e. 56