(a(i))[2]
State what a digital signal means.
(a(ii))[3]
State three advantages of digital transmission of data compared with analogue transmission.
(b(i).1)[1]
State the name of the blocks labelled $Y$.
(b(i).2)[1]
State the name of the block labelled $X$.
(b(ii))[2]
Describe the function of the parallel-to-serial converter.