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Question 1:

What is cosmic microwave background radiation?

A) Radiation emitted by stars in the Milky Way
B) Radiation from the Sun
C) Radiation leftover from the Big Bang
D) Radiation emitted by black holes

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Explanation: The correct answer is C) Radiation leftover from the Big Bang. Cosmic microwave background radiation is the residual heat radiation from the early stages of the universe, also known as the afterglow of the Big Bang.

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Question 2:

What is the temperature of cosmic microwave background radiation?

A) About -273°C
B) About 0°C
C) About 100°C
D) About 10,000°C

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Explanation: The correct answer is A) About -273°C. Cosmic microwave background radiation has an average temperature of approximately -273°C, which is just above absolute zero.

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Question 3:

Who discovered the cosmic microwave background radiation?

A) Arno Penzias and Robert Wilson
B) Albert Einstein
C) Edwin Hubble
D) Stephen Hawking

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Explanation: The correct answer is A) Arno Penzias and Robert Wilson. Arno Penzias and Robert Wilson discovered the cosmic microwave background radiation in 1965 while working at the Bell Telephone Laboratories.

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Question 4:

What does the cosmic microwave background radiation tell us about the early universe?

A) It provides evidence for the Big Bang theory
B) It reveals the existence of dark matter
C) It indicates the presence of black holes
D) It confirms the existence of multiple universes

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Explanation: The correct answer is A) It provides evidence for the Big Bang theory. The cosmic microwave background radiation is one of the strongest pieces of evidence supporting the Big Bang theory, as it is a remnant of the early stages of the universe.

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Question 5:

What is the primary source of cosmic microwave background radiation?

A) Photons released by primordial stars
B) Photons scattered by interstellar gas clouds
C) Photons emitted by active galactic nuclei
D) Photons from the recombination of hydrogen and helium atoms

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Explanation: The correct answer is D) Photons from the recombination of hydrogen and helium atoms. The primary source of cosmic microwave background radiation is the photons that were released when neutral hydrogen and helium atoms formed during the recombination era of the early universe.