Suppose $X$ has the following probability mass function $P(X=0)=0.2, P(X=1)=0.5, P(X=2)=0.3$. What is $E[X^2]$?

  • A
    $2.89$
  • B
    $1.7$
  • C
    $1.1$
  • D
    $1.21$

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