A firm targets $\backslash$pm $2\backslash$sigma quality control for its products. However, they ended up with $\backslash$pm $1\mathrm{.}5\backslash$sigma quality control. What is the $$expected number of defects$$ per batch size of $500$ in $\backslash$pm $1\mathrm{.}5\backslash$sigma quality control?

$102\mathrm{.}9$

$63\mathrm{.}3$

$133\mathrm{.}6$

$66\mathrm{.}8$