Question

Let x1, x2 x3 ....be a sequence of independent and identically distributed random variables, each having...

Let x1, x2 x3 ....be a sequence of independent and identically distributed random variables, each having finite mean E[xi] and variance Var(xi).
a)calculate the var (x1+x2)
b)calculate the var(E[xi])
c) if n-> infinite, what is Var(E[xi])?

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