ANSWER
The amplitude is
[tex]2[/tex]
EXPLANATION
The amplitude is the height of the function from the centre line which is
[tex]y = 0[/tex]
to the peak or trough of the graph, which is
[tex]y = 2[/tex]
This means that,
[tex]amplitude = |2 - 0| = 2[/tex]
Or
The amplitude is distance between the lowest point on the graph and the highest point on the graph divided by 2.
[tex]amplitude = \frac{1}{2} |2 - - 2| = \frac{1}{2} \times 4 = 2[/tex]