The separation energy of the electron present in the shell $n = 3$ is $1.51 \ eV$. What is the energy in the first excited state? ............ $eV$

The ratio of the wavelengths of the light absorbed by a Hydrogen atom when it undergoes $n=2 \rightarrow n=3$ and $n=4 \rightarrow n=6$ transitions,respectively,is

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$:
Assertion $A$: In the photoelectric effect,the electrons are ejected from the metal surface as soon as the beam of light of frequency greater than threshold frequency strikes the surface.
Reason $R$: When the photon of any energy strikes an electron in the atom,transfer of energy from the photon to the electron takes place.
In the light of the above statements,choose the most appropriate answer from the options given below:

Assertion : Angular momentum of an electron in any orbit is given by angular momentum $= \frac{nh}{2\pi}$,where $n$ is the principal quantum number.
Reason : The principal quantum number,$n$,can have any integral value.

The work function of $Cu$ is $7.68 \times 10^{-19} \ J$. If photons of wavelength $221 \ nm$ are made to strike the surface of the metal,the kinetic energy (in $J$) of the ejected electrons will be $\left(h=6.63 \times 10^{-34} \ Js, c=3 \times 10^8 \ ms^{-1}\right)$.

When an electron jumps from $L$ to $K$ shell,what happens to the energy?