[8 points] (a) Shown below is a multiplexer. Assume the data is transmitted right most character first (i.e., T is sent first in source 1). 1 2 3 4 SIHT AL GIB OWTENO (1)Draw a diagram showing the character data sent in each of the frames if the MUX is a synchronous TDM multiplexer. (2) Draw a diagram showing the character data sent in each of the frames if the MUX is an asynchronous TDM multiplexer with a frame size of three characters. (b) A company has its main computer in San Francisco, CA, and regional offices in New York, NY and Chicago, IL. The company has four 300 bps terminals in New York, and three 1200 bps, two 4800 bps, and two 9600 bps terminals in Chicago. The company wants to connect all of the New York terminals along with the Chicago terminals to a computer in San Francisco. Assume that all terminals require immediate access to the computers (i.e. no polling is allowed) and voice grade circuits with a maximum data rate of 33,600 bps are being used. The maximum data rate of a voice grade line using an FDM is 2000 bps. The maximum data rate of devices using an STDM equals twice the data rate of the voice grade line. The costs for each circuit is as follows: NY-Chicago $800/month, NY-San Francisco $1500/month, and Chicago-San Francisco $1200/month. The cost for the communications equipment is $25/month for each FDM, $50/month for each TDM, and $75/month for each STDM. [6 points] (1) Find the minimum cost network i.e., the one where the total cost of the communications circuits and equpment is the lowest, and draw a diagram of the configuration. [6 points] (2) The company wants to add two 1200 bps, and two 2400 bps terminal in New York to access the San Francisco computer. Find the new minimum cost network and draw a diagram of this configuration.