Question 1069701
The London Eye is a ferris wheel, with h(t)= a + b * cos(c * t)  
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The London Eye has a diameter of 135 meters and passengers board a cabin when theta = 0 degrees at a height of 2 meters above the ground
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The wheel has a radius of 135 / 2 = 67.5 meters so the height will oscillate about the center with amplitude of 67.5 meters
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The center of the wheel must be at 67.5 + 2 = 69.5 meters so the midline of the oscillation will be at 69.5 meters
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The wheel takes 30 minutes to complete one revolution so the height will oscillate with period 30 minutes
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Since the rider boards at the lowest point, the height will start at the smallest value and increase, this follows the shape of a flipped cosine curve
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Period is 30, so b = (2 * pi) / 30 = (pi / 15)
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we could use a transformation of either the sine or cosine function, so
we look for characteristics that would make one function easier than
the other.
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If we consider the graph of a cosine function that starts at the lowest height value, then
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we want cosine function because it starts at either the highest or lowest value,
while a sine function starts at the middle value.
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We know the cosine curve(in this case) was reflected because a standard cosine starts at the highest value, and this graph starts at the lowest value. 
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h(t) = -67.5 * cos( (pi/15) * t ) + 69.5
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That should get you started to get the answer
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