Answer: 5
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On the curve, the highest point has a y coordinate of y = 6
The lowest point on the curve has a y coordinate of y = -4
Subtracting the y values gets us: 6 - (-4) = 6 + 4 = 10
Cut that result in half: 10/2 = 5
The amplitude is 5. This is the vertical distance from the midline (y = 1) to either the highest point or the lowest point.