1. The sine and cosine function are sinusoidal waves such that they form waves when you graph them on a cartesian plane. The only difference between them is that the crest comes first followed by the trough in the sine function. The opposite is true for the cosine function. The graph in the picture is a sine function.
2. The amplitude is the measure from crest to crest, or from trough to trough. The amplitude in the graph is 1.5.
3. The period is the reciprocal of amplitude. Therefore,itis 1/1.5 or 2/3.
4. There is no horizontal displacement because the wave only moves in a vertical direction.
5. The vertical displacement is from crest to trough which is 1 unit.