1 .
I flip a fair coin, independently, $n$ times. For each heads, you win \$3, whereas for each tails,
you lose \$1. Define the random variable $X$ to be the amount of dollars that you win. What is the
expected value of $X$?
(a)
$n$
(b)
$2n$
(c)
$n/2$
(d)
$3n/2$