Question 1199333
since the rider is boarding at the middle between the bottom and the top and heading for the top of the ferris wheel, then the sine function is indicated.


general form of the sine function is y = a * (b * (x - c)) + d
a is the amplitude
b is the frequency
c is the horizontal shift
d is the vertical shift


the period of the cycle needs to be 30 seconds.
that's the time required to make one complete revolution.
frequency = 360 / period = 360 / 30 = = 12


the ferris wheel has a diameter of 20 meters.
that means a radius of 10 meters.
the amplitude of the sine wave is therefore 10 meters.


the center of the circle is 11 meters off the ground.
that means the vertical shift is 11 meters.


there is no horizontal shift.


the sine wave formula becomes y = 10 * sin(12 * x) + 11
that would be selection c.


here's the graph showing 2 cycles of the ferris wheel.


<img src = "http://theo.x10hosting.com/2022/122202.jpg">