When the excited electron of a $H$ atom from $n=5$ drops to the ground state,the maximum number of emission lines observed are $.......$

If the wavelength for an electron emitted from $H$ atom is $3.3 \times 10^{-10} \ m$,then energy absorbed by the electron in its ground state compared to minimum energy required for its escape from the atom,is $.......$ times. (Nearest integer).
[Given $: h = 6.626 \times 10^{-34} \ Js$,Mass of electron $= 9.1 \times 10^{-31} \ kg$ ]

In $H$ atom,an orbit has a diameter of about $16.92 \ \mathring{A}$. What is the maximum number of electrons that can be accommodated in this orbit?

Match the following columns:

Column-$I$	Column-$II$
$(1)$ Photon	$(A)$ Value of $4$ for $N$ shell
$(2)$ Electron	$(B)$ Probability density
$(3)$ $\psi^2$	$(C)$ Always $+$ value
$(4)$ Principal quantum number $(n)$	$(D)$ Represents wavelength and momentum

Match the items in Column-$A$ with the items in Column-$B$.

Column-$A$	Column-$B$
$(1)$ Dalton	$(A)$ Photoelectric effect
$(2)$ Maxwell	$(B)$ Wave theory
$(3)$ Huygens	$(C)$ Atomic theory
	$(D)$ Electromagnetic radiation

In which of the following transitions is one quantum of energy emitted?