12. In a particular game, a fair die is tossed. If the number of spots showing is either 4 or 5 you win
$1； if the number of spots showing is 6 you win S4； and if the number of spots showing is 1, 2, or 3, you win nothing. Let X be the amount that you win. The expected value of X is
(A) $0.00.
(B) $1.00.
(C) $2.50.
(D) $4.00.
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