I am looking just for the answer for the final part of the question: prove that the variance does not exit for beta

Please see attached.

8. The Pareto distribution, with parameters a and 3, has pdf BaB fx (x) = roti , a 0 , B >0 . show that fx (x) is a pdf. . Derive the mean and variance of this distribution. . Prove that the variance does not exist if 3