In a satellite radio system, 128 stations of stereo quality are to be packaged in one data stream. For each station, two(left and right) signals of bandwidth 15,000 hz are sampled, quantized, and binary coded into PCM signals. The transmitter must multiplex the data from the 128 stations into a single stream via time multiplexing.

A: If the maximum acceptable quantization error in sample amplitudes is 0.25% of the peak signal voltage, find the minimum number of bits needed for a uniform quantizer.

B: If the sampling rate must be 20% higher than the Nyquist rate, find the minimum bit rate of the multiplexed data stream based on the quantizer of part(A).

C: If 5% more bits are added to the multiplexed data for error protection and synchronization, determine the minimum bandwidth needed to transmit the final data stream to receivers.

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg.m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?