Answer:
Choice A
Explanation:
The lower the point the higher the kinetic energy because Mechanical energy is conserved and the Gravitational Potential Energy gets lower when the height is lower
Answer:
Friction 100 j
Explanation:
Friction causes the inequality between PE and KE
100 J
At the point of maximum displacement (a), the elastic potential energy of the spring is maximum:

while the kinetic energy is zero, because at the maximum displacement the mass is stationary, so its velocity is zero:

And the total energy of the system is

Viceversa, when the mass reaches the equilibrium position, the elastic potential energy is zero because the displacement x is zero:

while the mass is moving at speed v, and therefore the kinetic energy is

And the total energy is

For the law of conservation of energy, the total energy must be conserved, therefore

. So we can write

that we can solve to find an expression for v:
In Electromagnetic spectrum, X-rays has very high frequency but gamma-rays has more than that. If you consider cosmic rays as an electromagnetic wave, then it would be highest energetic and has highest frequency.
In short, Your Answer is "Cosmic rays"
Hope this helps!