GROWTH DEVELOPMENT CHILD
SUMMATIVE ASSESSMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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hydrogen, helium, and dark matter
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gold and plutonium
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oxygen and water vapor
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carbon
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Detailed explanation-1: -Using powerful telescopes, scientists have made extensive spectroscopic surveys of distant stars and galaxies. The data indicates that hydrogen and helium make up nearly all of the nuclear matter in the universe. The most abundant element, hydrogen, accounts for 74% of the mass while helium contributes 25%.
Detailed explanation-2: -It turns out that roughly 68% of the universe is dark energy. Dark matter makes up about 27%. The rest-everything on Earth, everything ever observed with all of our instruments, all normal matter-adds up to less than 5% of the universe.
Detailed explanation-3: -The abundance of chemical elements in the universe is dominated by the large amounts of hydrogen and helium which were produced in the Big Bang. Remaining elements, making up only about 2% of the universe, were largely produced by supernovae and certain red giant stars.
Detailed explanation-4: -By precisely measuring the distribution of X-rays from the hot gas, the astronomers were able to make the best measurement yet of the distribution of dark matter near the center of a galaxy cluster.