The ozone layer in the Earth's atmosphere is essential for the protection of human life because it...

Arrange the following in the ascending order of wavelength :
$(A)$ Gamma rays $(\lambda_1)$
$(B)$ $X$-rays $(\lambda_2)$
$(C)$ Infrared waves $(\lambda_3)$
$(D)$ Microwaves $(\lambda_4)$
Choose the most appropriate answer from the options given below :

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

In household appliances,which waves are used to operate remote control switches?

What is the approximate wavelength range of the electromagnetic spectrum?

The frequency range from $3 \times 10^9 \, Hz$ to $3 \times 10^{10} \, Hz$ is known as: