Ultra high frequency $(UHF)$ band stands for

The height of a $T.V.$ tower is $75 \ m$. What is the maximum distance in $km$ up to which $T.V.$ transmission can be received (in $.98$)? (Radius of the Earth $= 6.4 \times 10^6 \ m$).

$A$ carrier wave of peak voltage $12 \,V$ is used to transmit a signal. If the modulation index is $75 \%$, the peak voltage of the modulating signal is (in $\,V$)

Which waves can be transmitted more efficiently by an antenna?

The frequency range for commercial $FM$ radio broadcasting is .......

For efficient transmission of sound waves of wavelength $\lambda$,the minimum length of the antenna should be.....