a) Sam owns shares of stock S and stock T in her portfolio. The total value of her stock S shares is 3,000. The total value of her stock T shares is 7,000. The table below shows the different states of the economy, the probabilities, and the returns for each stock, for the upcoming year. Calculate: i) The expected return on stock S ii) The expected return on Alis portfolio ili) The standard deviation of her portfolio

\begin{tabular}{c|ccc} \hline State of the economy & Probability & Return on stock T & Return on stock S \\ \hline Boom & 10% & 18% & 2% \\ Normal & 50% & 6% & 5% \\ Bust & 40% & 17% & 11% \\ \hline \end{tabular}