What is the shortest wavelength present in the Paschen series of spectral lines?
1. \(818.9~\text{nm}\)
2. \(779~\text{nm}\)
3. \(500~\text{nm}\)
4. \(1024~\text{nm}\)

A difference of \(2.3\) eV separates two energy levels in an atom. What is the frequency of radiation emitted when the atom makes a transition from the upper level to the lower level?
1. \(6.6\times10^{14}\) Hz
2. \(5.6\times10^{14}\) Hz
3. \(9.3\times10^{14}\) Hz
4. \(7.9\times10^{14}\) Hz

A hydrogen atom initially in the ground level absorbs a photon, which excites it to the \(n=4\) level. The wavelength of the photon is: