Kali's Ski Resort, Inc. stock is quite cyclical. In a boom economy, the stock is expected to return $30\%$ in comparison to $12\%$ in a normal economy and a negative $20\%$ in a recessionary period. The probability of a recession is $15\%.$ There is a $30\%$ chance of a boom economy. The remainder of the time, the economy will be at normal levels. What is the standard deviation of the returns on Kali's Ski Resort, Inc. stock?