Answer:

Explanation:
Here we can use energy conservation
As per energy conservation conditions we know that work done by external source is converted into kinetic energy of the disc
Now we have

now we know that work done is product of force and displacement
so here we have


now for moment of inertia of the disc we will have



now from above equation we will have


The block that has a higher temperature describes the thermal energy of these blocks. Thermal energy is a measure of internal energy - therefore, the block with the higher temperature has more internal energy than the block with the lower temperature, meaning it's thermal energy is greater.
You can find the mass of an atom by adding the number of protons and neutrons. In this case the atom has 2 protons and 3 neutrons so the mass is 5.
To answer these questions just use the equations for potential energy using the mass and heights described. the potential energy at the prescribed heights = the initial kinetic energy required to reach that height.
Make sure you calculate the force of gravity on the surface using the radius of the planet.