2. (35 pts) In a wireless communication system, the received power at a distance of d meters is modeled by Pr = where Pr is the transmitted signal power, and X is an exponential random variable with PDF fx(x) = { Se", 20 0, otherwise (3) The outage probability P(PRT) is defined as the probability that the received signal power falls below a certain threshold 7. (a) Find an expression for the outage probability as a function of Prid.T. (b) Find the limits of the outage probability for the six cases d 0,0 , Pr + 0, Pr ? 0,7 ? 0, T . For each case, assume the remaining parameters are fixed and finite (For example, for d 0, assume Pr and 7 are both fixed and finite).