PLEASE READ THE FOLLOWNG INSTRUCTONS CAREFULIY: 1- This exam has a total of 9 pages (including the cover page). 2- There are 4 questions and the credit for each question is printed with the question number. 3. All questions should be answered on the same sheets. Question 1 [10 marks] Q 1.1. Choose the correct answer (5 Marks) 1. In fiber optics, the signal is waves. A) Radio B) Light C) infrared D) Very low-frequency 2. If the maximum amplitude of a sine wave is 5v, the minimum amplitude is v. A) 5 B) 1 C) 5 D) Between 5 and 5 3. The of a composite signal is the difference between the highest and the lowest frequencies contained in that signal. A) period B) Bandwidth C) Frequency D) Amplitude 4. The data rate is sometimes called the rate. A) Bit B) Baud C) Signal D) Information 5. is a type of transmission impairment in which an outside source such as crosstalk corrupts a A) Noise B) Distortion C) Attenuation D) Decibel 6. Fora channel, the Nyquist bit rate formula defines the theoretical maximum bit rate. A) low-pass B) Bandpass C) Noisy D) Noiseless 7. The is the physical path over which a message travels. A) Protocol B) Signal C) Medium D) Bandwidth 8. is the set of techniques that allows the simultaneous transmission of multiple signals across a single data link. A) Demodulating B) Multiplexing C) Compressing D) Signal encoding 9. In . each packet is treated independently of all others. A) Circuit switching B) Datagram switching C) Frame switching D) Virtual circuit switching 10. In , the stations share the bandwidth of the channel in time. A) FDMA B) CDMA C) TDMA D) OFDMA Q 1.2. Match the following to one type of multiplexing. (2 Marks) Q 1.3. Match the following to one type of switching (Datagram packet switching, Circuit switching, Virtual circuit packet switching). a- Question 2 Q 2.1. Answer the following questions a- If the bit rate for a 64-QAM signal is 6000 bps, what is the baud rate? b. Give an example of digital-to-analog conversion. Q 2.2. Suppose that the channel bandwidth B=3MHz. a- For SNRdB=25dB, what is the theoretical maximum channel capacity C (Mbps)