(a(i))[2]
State the meaning of a digital signal.
(a(ii))[1]
State one adjustment to the sampling process or to the ADC that improves the accuracy of reproduction of the original analogue signal.
(b)[1]
The least significant bit in the four-bit digital number $1100$ corresponds to a signal voltage of $2.5\,\text{mV}$. Calculate the signal voltage, in $\text{mV}$, represented by this digital number.