When an electron jumps down from 5th Bohr orbit to 3rd Bohr orbit in H-atom, then how many numbers of spectral lines will be formed?

An electron jumps from fourth to first orbit in an atom. How many maximum number of spectral lines can be emitted by the atom ?

According to Bohr's theory, when an electron jumps from any higher orbit to the third orbit, spectral lines are emitted. These are called

Radius of 3^(rd) Bohr orbit of hydrogen atom

The transition of electron occurs in H-atom from 6^(th) to 3^(rd) orbit. The number of spectral lines given are

To energise an electron from 1st Bohr orbit to the 3rd Bohr orbit for Li^(2+) ion, what is the required energy?