What is plum pudding model of the atom ? 

According to classical theory, Rutherford atom was

As an electron makes a transition from an excited state to the ground state of a hydrogen - like atom/ion

Which of the following statements are true regarding Bohr's model of hydrogen atom

$(I)$ Orbiting speed of electron decreases as it shifts to discrete orbits away from the nucleus

$(II)$ Radii of allowed orbits of electron are proportional to the principal quantum number

$(III)$ Frequency with which electrons orbits around the nucleus in discrete orbits is inversely proportional to the principal quantum number

$(IV)$ Binding force with which the electron is bound to the nucleus increases as it shifts to outer orbitsSelect correct answer using the codes given belowCodes :

In the following diagram, which particle has highest $e/m$ value?

The following diagram indicates the energy levels of a certain atom when the system moves from $4E$ level to $E$. A photon of wavelength $\lambda _1$ is emitted. The wavelength of photon produced during it's transition from $\frac{7}{3}E$ level to $E$ is $\lambda_2$. The ratio $\frac{{{\lambda _1}}}{{{\lambda _2}}}$ will be