Science-Space-04-ID
Mr. Sander explained to his 6th-grade science students, "Most astronomers believe the theory that the universe began in a Big Bang about 14 __________ years ago."
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- thousand
- million
- billion
Mr. Sander explained to his 6th-grade science students, "Most astronomers believe the theory that the universe began in a Big Bang about 14 __________ years ago."