Let XXX have PMF P(X=k)=1/3P(X=k) = 1/3P(X=k)=1/3 for k∈{1,2,3}k \in \{1, 2, 3\}k∈{1,2,3}. What is E[X2]E[X^2]E[X2]?
14/3
2
2.5
3