Answer:
The energies corresponding to each of the allowed orbitals are called energy levels.
Explanation:
A scientist known as Niels Bohr put forward that electrons in an atom covers some permitted orbitals with a specific energy. In other words, the energy of an electron in an atom is not continuous, but 'quantized.' The energies corresponding to each of the allowed orbitals are called energy levels.

Answer:
240N
Explanation:
The formula for force is F=mass×acceleration.
Therefore, Force= 120×2= 240N
It would last as long as the applied force continued, or until the accelerating object hit something.
Answer:
Plato, Aristotle developed it further and used for 1400 years till Copernicus.
Explanation: