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Which of these are correct formulas for Expectation and Variance?

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$\\begin{align*}
E[aX+b] &= aE[X] + b \\\\
Var[aX+b] &= a^2 Var[X] + 0 \\\\
E[Y] &= E[E[Y|X]] \\\\
Var[Y] &= E[Var[Y|X]] + Var[E[Y|X]]
\\end{align*}$

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