Hi there!
We can use the following equation for constant velocity:

d = displacement (m)
v = velocity (m/s)
t = time (s)
Plug in the givens:

Nuclear energy is energy that is stored in the core of a certain type of atom. Atoms are the smallest units of matter and they make up everything in our universe. Energy is what causes the core of an atom to stay together and inside the core, there is vast amounts of energy.
All describe an objects motion except : mass
Answer:
U
Explanation:
The first law of thermodynamics states that:

where
U is the internal energy of the gas, which represents the sum of the chemical and thermal energy stored in the atoms and molecules of the gas
represents the variation of internal energy
Q is the heat absorbed by the system
W is the work done by the system
So, the sum of the chemical and thermal energy stored in atoms and molecules is represented by U, the internal energy.