Given the following information, what is the standard deviation for this stock?

$($hint you'll need to find the expected return first$)$

Probailities:

Recession: $0\mathrm{.}3$

Normal: $0\mathrm{.}5$

Boom: $0\mathrm{.}2$

Returns:

Recession :$-12\%$

Normal: $13\%$

Boom: $25\%$