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when was the sound barrier broken for the first time
It was in the X-1 that Chuck Yeager was credited with being the first person to break the sound barrier in level flight on October 14, 1947.
at what altitude did chuck yeager become the first person to break the sound barrier
Chuck Yeager was credited with being the first person to break the sound barrier in level flight flying at an altitude of 45,000 ft.

Question: where
Self-contained rewrite: where did chuck yeager the sound barrier broken for the first time