Final answer:
The amplitude of a wave is the maximum displacement from its equilibrium position. For a wave with a crest 2 meters above the still water mark, the amplitude is 1 meter, since the amplitude is half the height from crest to equilibrium.
Step-by-step explanation:
The question is asking about the amplitude of a wave, which is a fundamental concept in the study of waves in physics. Amplitude refers to the maximum displacement of the medium from its equilibrium position. For example, if a wave has a crest that is 2 meters above the still water mark, the amplitude of the wave would be half that distance, so the amplitude would be 1 meter.
Similarly, looking at other wave examples such as a wave function or a sound wave wherein the amplitude represents how 'loud' the sound is, we can understand amplitude as describing the energy or intensity of the wave.
The correct option for the amplitude of a wave where the crest measures 2 meters above the still water mark is 1 meter, since the height of the wave is twice the amplitude. Therefore, if the amplitude was specifically requested, we would need to take half of the height measurement—between the crest and the equilibrium level—to find it.