please answer 5.4 and thank u so much.

Q5 4 Points The inter-arrival time of market shocks is modeled by an exponential distribution with pdf f(x) = ze ", > > 0. Consider a random sample {X1, . .. , An} from this distribution.Q5.4 1 Point Let of be the sample variance of the random sample. What is Ed ? Is the sample standard deviation o x an unbiased estimator for 0? Enter your answer here