Daniel B. answered 04/12/23
A retired computer professional to teach math, physics
Amplitude is always the radius of the wheel, which is 17.5 m.
Midline is the distance of the center of the wheel from the height of 0.
That is the radius plus the elevation of the wheel -- 17.5 + 3 = 20.5 m
Period is the time to make one revolution -- 8 min.
After 4 minutes you have completed half a turn.
So if you started at the bottom, then after 4 minutes you will be at the top.
The height of the top is the diameter of the wheel plus the wheel's elevation --
35 + 3 = 38 m