In a sample of hydrogen atoms, electrons are de-excited from the 4th excited state to the ground state. Which is/are correct statement(s)?

Q. In a sample of H-atoms, electrons are de-excited from 4th excited state to ground state. Which is/are correct statement(s)?

Q. In a sample of H-atoms, electrons are de-excited from its 4th excited state to the ground state. Which is an incorrect statement?

Q. In a sample of hydrogen atom in ground state electrons make transition from ground state to a particular excited state where path length is five times de-broglie wavelength, electrons make back transition to the ground state producing all possible photons. If photon having 2nd highest energy of this sample used to excite the electron in a particular excited state of $L{i}^{2+}$ ion then find the final excited state of $L{i}^{2+}$ ion

Q. In a sample of H-atoms, if electrons make transition from $4^{th}$ excited state to $2^{nd}$ state then:

Q. In a sample of hydrogen atom in ground state, electrons make transition from ground state to a particular excited state where path length is five times de-broglie wavelength, electrons make back-transition to the ground state producing all possible photons. If photon having 2nd highest energy of this sample can be used to excite the electron in a particular excited state of $L{i}^{2+}$ atom then find the final excited state of $L{i}^{2+}$ atom