What is the angular momentum of an electron when it revolves in orbits?

Write the postulates of Bohr's model of the hydrogen atom.

Which of the following relations is applicable for any $H$-like species?

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.

If $n=2$ for $He^{+}$ ion,then what is the wavelength in $\mathring{A}$?

If the series limit of wavelength of the Lyman series for the hydrogen atom is $912 \ \mathring{A}$,then the series limit of wavelength for the Balmer series of radiation which may be emitted is :