Which of the following electromagnetic waves has the longest wavelength?

Match List-$I$ with List-$II$.

List-$I$	List-$II$
$(a)$ $10\, km$ height over earth's surface	$(i)$ Thermosphere
$(b)$ $70\, km$ height over earth's surface	$(ii)$ Mesosphere
$(c)$ $180\, km$ height over earth's surface	$(iii)$ Stratosphere
$(d)$ $270\, km$ height over earth's surface	$(iv)$ Troposphere

$TV$ waves have a wavelength range of $1-10 \, m$. Their frequency range in $MHz$ is

Which is the correct ascending order of wavelengths?

Which of the following groups of electromagnetic waves is in increasing order of frequency?

$A$ monochromatic source of light operating at $15 \text{ kW}$ emits $2.5 \times 10^{22} \text{ photons/s}$. The region of an electromagnetic spectrum to which the emitted electromagnetic radiation belongs to . . . . . . . (Take $h = 6.6 \times 10^{-34} \text{ J}\cdot\text{s}$ and $c = 3 \times 10^8 \text{ m/s}$).