Representing a transmission line by the two-port network, in terms of \(A B C D\) parameters,

(a) express \(V_{S}\), which is the sending-end voltage, in terms of \(V_{R}\), which is the receiving-end voltage, and \(I_{R}\), the receiving-end current, and

(b) express \(I_{S}\), which is the sending-end current, in terms of \(V_{R}\) and \(I_{R}\).

(a) \(V_{S}=\) ________

(b) \(I_{S}=\)________