a) Prove that the power of s(t) = 10 cos(10t) + 20 cos(206) is equal to 250 Watts. b) Identify a communication system. For the communication system of your choice, state the name of your communication system, and its primary application. c) Identify each of the following components, • The Source - Include as much information as possible, e.g. typical source data, analog or digital, real-time or non-real-time and an explanation where necessary) • The Channel - Include the physical medium and characteristics of the transmitted signal • The Sink - Include the data's intended purpose Draw a block diagram incorporating (at least) all the above. d) Give the bandwidth and signal modulation type used in this system, specifically identify whether analog or digital modulation. Where possible explain what aspect(s) of the signal is being modulated.