Answer:
2n² means 2 × n × n . the power on the n represent the no. of time it is multiplied.
for ex 3x² = 3 × x × x
4x⁴ = 4 × X× X × X× X
If the moon did not rotate we would see all hemispheres of the moon as it revolves around the Earth and not just the phases.
Atoms return to their ground state by emitting a photon of light.
