If ${\mathrm{\nu }}_1$ is the frequency of series limit of Lyman series, ${\mathrm{\nu }}_2$ is the frequency of the first line of Lyman series and ${\mathrm{\nu }}_3$ is the frequency of series limit of Balmer series, then which of the following equation is correct?

Suppose that a hypothetical atom gives a red, green, blue & violet line spectrum. Which jump according to the figure would give off the red spectral line?

If$\mathrm{I}, \mathrm{II}, \mathrm{III} \& \mathrm{IV}$ are the first $4$lines in Lyman series of the hydrogen spectrum. Which of the following is true:

(a) The frequency difference between $\mathrm{I} \text{and} \mathrm{II}$ is greater than $\mathrm{II} \text{and} \mathrm{III}$.

(b) Energy of photon: $\mathrm{I}>\mathrm{II}>\mathrm{III}>\mathrm{lV}$

(c) Wave number: $\mathrm{I}>\mathrm{II}>\mathrm{III}>\mathrm{lV}$

(d) The wavelength difference between $\mathrm{I} \text{and} \mathrm{II}$ is greater than $\mathrm{II} \text{and} \mathrm{III}$.