It is situated in period number 1.
The correct answer is
<span>b. increases with the square of speed
In fact, the kinetic energy of a moving object is given by
</span>

<span>where m is the mass of the object and v is its speed. We see that the kinetic energy is directly proportional to the square of the speed, therefore option B is the correct one.</span>
C the thermal equilibrium
Answer:
S=48.29 m
Explanation:
Given that the height of the hill h = 2.9 m
Coefficient of kinetic friction between his sled and the snow μ = 0.08
Let u be the speed of the skier at the bottom of the hill.
By applying conservation of energy at the top and bottom of the inclined plane we get.
Potential Energy=kinetic Energy
mgh = (1/2) mu²
u² = 2gh
u²=2(9.81)(2.9)
=56.89
u=7.54 m/s
a = - f / m
a = - μ*m*g / m
a = - μg
From equation of motion
v²- u² = 2 -μ g S
v=0 m/s
-(7.54)²=-2(0.06)(9.81)S
S=48.29 m