(a(i))[1]
From Fig. 6.2, find the four-bit number that the ADC gives at time $0.25\,\text{ms}$.
(a(ii))[1]
From Fig. 6.2, find the four-bit number that the ADC gives at time $1.25\,\text{ms}$.
(b)[4]
The digital number is sent and then changed into an analogue form by the digital-to-analogue converter (DAC). Using the data in Fig. 6.2, draw the DAC output level on the axes in Fig. 6.3 for $t = 0$ to $t = 1.50\,\text{ms}$. Assume that the signal transmission between point $P$ and the DAC output involves no time delay.