QUESTION 3 Select the correct statement(s) regarding baseband signal modulation. a. modulation involves the mixing a baseband signal with a carrier to produce a modulated passband signal b. modulation techniques are only required for analog information signals, since digital signals are represented by discrete logical values of "1" and "O" c. modulation eliminates the baseband signal's frequency bandwidth, thus enabling greater efficiencies when transmitting a modulated carrier signal d. all statements are correct QUESTION 4 Which carrier signal variables are used to represent baseband message/information in the modulation process? a. amplitude, bandwidth, time b. amplitude, frequency, temperature c. frequency, logical encoding variables, timing d. amplitude, frequency, phase angle QUESTION 5 A carrier wave has an amplitude of 2 volts, a frequency of 120 kHz, and -1/2 radian phase angle. Select the correct carrier wave equation. a. c(t) = 2 cos(21*12kHz*t - TT) b. c(t) = 2cos(21*120E3Hz*t + TT) c. c(t) = 2cos(21*120E3Hz*t - 1.57) d. None of the above are correct QUESTION 18 Given the following FM modulated signal equation, determine the original message equation, m(t). s(t)= 1cos(212.4GHz*t + 5sin(217 kHz*t)), Kvco=4500 (Hz/v) a. m(t)= 1.8cos(22.4E9t) b. m(t)= 1.8cos(2122E3t) c. m(t)= 14.7cos(217kHz*t) d. m(t)= 7.78cos(217kHz*t)