An airplane's altitude can be described as a function of time, since for each moment (input, time), there is a specific altitude (output). This relationship changes during the different phases of flight: ascent, cruise, and descent. Therefore, altitude varies with time in a functional manner. ;
An airplane's altitude is a function of time, as each moment corresponds to a specific altitude. This relationship varies during different phases of flight: ascent, cruise, and descent. Therefore, the altitude can be plotted against time to show this functional relationship.
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