How much energy is needed to release the electron from the second excited state in the hydrogen atom (in $eV$)?

The energy levels of a certain atom are $A, B,$ and $C$ in increasing order of energy,i.e.,$E_A < E_B < E_C$. If $\lambda_1, \lambda_2,$ and $\lambda_3$ are the wavelengths of radiation corresponding to transitions from $C$ to $B$,$B$ to $A$,and $C$ to $A$ respectively,which of the following relations is correct?

If the binding energy of the electron in a hydrogen atom is $13.6 \ eV$,the energy required to remove the electron from the first excited state of $Li^{++}$ is.....$eV$.

The ratio of the energies of the electron in the hydrogen atom in the first and second excited states is

In Bohr's atomic model of hydrogen,let $K$,$P$ and $E$ be the kinetic energy,potential energy and total energy of the electron,respectively. Choose the correct option when the electron undergoes transitions to a higher level.

For a certain hypothetical one-electron atom,the wavelength (in $\mathring{A}$) for the spectral lines for transition from $n = p$ to $n = 1$ is given by $\lambda = \frac{1500p^2}{p^2 - 1}$ (where $p > 1$). The ionization potential of this element must be ......$V$ (Take $hc = 12420 \text{ eV-} \mathring{A}$).