Which series of the hydrogen spectrum was observed first?

Specify the quantum number for the limit wavelength of the spectral series of a hydrogen atom.

The shortest wavelength in the Lyman series is $912 \ \text{Å}$. Then, the longest wavelength in the series must be (in $\text{Å}$)

The lines in the Balmer series have their wavelengths lying between

$A$ hydrogen atom is excited from the ground state to a state with principal quantum number $n = 4$. The number of spectral lines emitted in the emission spectrum is:

In hydrogen spectrum,which of the following spectral series lies in the ultraviolet region?