Light of wavelength $1 \,nm$ belongs to the following class of waves:

Which of the following electromagnetic radiations has the smallest wavelength?

Electromagnetic waves with wavelengths ranging from $3 \times 10^{-3} \, m$ to $1 \, m$ are used in satellite communication. What is the corresponding frequency range? (Given $c = 3 \times 10^8 \, m/s$)

$(i)$ The wavelength of microwaves is greater than that of $UV$-rays.
$(ii)$ The wavelength of $IR$ rays is less than that of $UV$-rays.
$(iii)$ The wavelength of microwaves is lesser than that of $IR$ rays.
$(iv)$ Gamma rays have the shortest wavelength in the electromagnetic spectrum.
Of the above statements:

What protects us from $UV$ light emitted by the Sun?

Write a short note on light.