The bandwidth of an optical fiber is

An information signal of frequency $10 \text{ kHz}$ is modulated with a carrier wave of frequency $3.61 \text{ MHz}$. The upper sideband and lower sideband frequencies are:

$A$ $TV$ tower has a height of $150 \ m$. If the population density around the $TV$ tower is $10^3 \ km^{-2}$, then the population covered by the tower is (Radius of the earth, $R = 6.4 \times 10^6 \ m$). (in $\text{lakh}$)

Which type of medium is used for optical communication?

In a frequency modulated wave:

The modulation index of an $FM$ carrier having a carrier swing of $200\, kHz$ and a modulating signal frequency of $10\, kHz$ is: