the direction of the current in an alternating current circuit changes repeatedly at a constant rate. the often-ness with which it changes is known as its frequency .
in this question, we have given,
we will first calculate displacement of jetliner when speed is constant
from second equation of motion we know that,
now calculate displacement s' when it is decelerating
therefore total displacement=s+s'
the first one is high roller, the second one is singapore flyer, the third one is giant wheel.