8.3 by using the form of the channel de ned in equation (8.46), plot a hundred random qpsk constellation points and the magnitude squared of the fft (and use zero-padding to smooth the shape) of the channel for a single draw for a given channel de ned by (a) no delay spread, (b) k = 0: 3, (c) k = 1, (d) k = 3, (e) k = 10, (f) k = 25.

Ahe-xe mixture containing a 0.75 mole fraction of helium is used for cooling electronics in an avionics application. at a temperature of 300 k and atmospheric pressure, calculate the mass fraction of helium and the mass density, molar concentration and molecular weight of the mixture. if the cooling capacity is 10 l, what is the mass of the coolant?