If XXX is a random variable such that P(X=k)=12kP(X=k) = \frac{1}{2^k}P(X=k)=2k1 for k=1,2,…k=1, 2, \dotsk=1,2,…, what is the value of E[X2]E[X^2]E[X2]?
222
444
666
333