sound_staging_有道手机词典

1.That staging point is expected to come at about the 124-second mark, when the supersonic Ares I-X rocket is traveling Mach 4.7? More than four times the speed of sound, its Max speed for the flight.
分离时刻预计在124秒时，这时超音速火箭战神i - X以4.7马赫的速度飞行——这是音速的四倍，也是飞行的最高速度。
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