(a)[2]
Suggest two roles of the copper braid.
(b)[2]
Suggest two reasons why a wire pair is usually not used to link the aerial to the receiver.
(c)[4]
A coaxial cable that links an aerial to a receiver has a length of $14\,\text{m}$. Its attenuation per unit length is $190\,\text{dB km}^{-1}$. Calculate the fractional loss in signal power while the signal travels along the cable.