[Q]: Why do satellites and spacecraft launched from Earth need to reach a specific speed to escape Earth's surface?
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[A]: to overcome Earth's gravitational force

[Q]: A 10 g sample of aluminum and a 10 g sample of iron were each heated by 100 joules of energy. The temperature of the aluminum sample rose 11C, while the temperature of the iron sample increased 23C. Which statement best accounts for these results?
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[A]: The specific heat of iron is less than that of aluminum.

[Q]: In addition to oxygen, which gases make up the largest percentage of Earth's atmosphere?
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[A]:
carbon dioxide, water vapor, and nitrogen