Which series of the hydrogen spectrum lies in the visible region?

The transition from the state $n = 3$ to $n = 1$ in a hydrogen-like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from

In an $H$-like atom,when an electron transits from energy state $n=5$ to $n=2$,a photon of wavelength $434 \, nm$ is emitted. What will be the wavelength of the photon emitted when the transition occurs from energy state $n=4$ to $n=2$?

$A$ hydrogen atom is excited from the ground state to another state with a principal quantum number equal to $4$. The number of spectral lines in the emission spectra will be:

If $R$ is the Rydberg constant in $cm^{-1}$, then the hydrogen atom does not emit any radiation of wavelength in the range of

The electron in a hydrogen atom in a sample is in the $n^{th}$ excited state. The number of different spectral lines obtained in its emission spectrum will be: