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1 . Let $S$ be a uniformly random 2-element subset of $\{1,2,3,4\}$, and let $X$ be the number of elements of $S$ that are even. What is the expected value $\mathbb{E}(X)$ of $X$?
(a)
2
(b)
3/2
(c)
5/2
(d)
1