Odometer: tells you the distance traveled by vehicle since it was new (or when last reset)
Speedometer: tells you the velocity of the vehicle at that moment.
This question involves the concepts of the law of conservation of energy and kinetic energy.
The girl's fastest speed is "3.7 m/s".
According to the law of conservation of energy, the girl will have the fastest speed at mean position, which will be calculated as follows:
Loss in Potential Energy = Gain in Kinetic Energy

where,
v = maximum speed = ?
g = acceleration due to gravity = 9.81 m/s²
Δh = change in height = 1.3 m - 0.6 m = 0.7 m
Therefore,

<u>v = 3.7 m/s</u>
<u></u>
Learn more about the Law of Conservation of Energy here:
brainly.com/question/381281?referrer=searchResults
The force required is
(15 kg) x (the acceleration, in m/s²) newtons.