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Correct answer
D. The Pointer Stars
Explanation
The Pointer Stars is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
B. Radio waves
Explanation
Radio waves is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
D. Spleen
Explanation
Spleen is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
A. 100,000
Explanation
100,000 is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
A. Yellow draft
Explanation
Yellow draft is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
D. a series of refractions
Explanation
Twinkling of stars is due to atmospheric refraction. There are different layers in the atmosphere with varying temperature and density. This results in the variation of refractive index of the atmosphere with time. So, when the light from a star passes through these different layers, it experiences different levels of refraction. Thus, the image of the star gets distorted constantly in brightness and position which makes the star look like its twinkling.
Correct answer
B. Hydrogen and Helium
Explanation
The Sun is a huge ball of hydrogen and helium held together by its own gravity.
Correct answer
D. Exploration Extravehicular Mobility Unit (xEMU)
Explanation
Exploration Extravehicular Mobility Unit (xEMU) is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
B. Energy quanta
Explanation
Energy quanta is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
A. Must be either expanding or contracting
Explanation
Must be either expanding or contracting is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.