$A$ communications Earth satellite:

The bit rate for a signal,which has a sampling rate of $8 \, kHz$ and where $16$ quantisation levels have been used,is ......... $bits/sec$.

The government has divided the frequency range from $30\ MHz$ to $60\ MHz$ between $20$ stations,which are independently beaming their signals. Which of the signals can be beamed by each of the stations?

If a message signal of frequency $f_{m}$ is amplitude modulated with a carrier signal of frequency $f_{c}$ and radiated through an antenna,the wavelength of the corresponding signal in air is ....... .

$A$ carrier signal $60 \sin(2\pi \times 10^6 t)$ is used to modulate an audio signal $15 \sin(300 \pi t)$. The depth of modulation is .......... $\%$.

The range of frequency bands used for standard $AM$ broadcast is