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2. Delta Airlines is reporting its first quarter earnings next Wednesday April 15th before the market open. As such, Walker is forecasting DAL's one-week return, assuming that he is holding DAL today until Wed 4-15. Given the coronavirus crisis, Walker estimates that there is 10% chance that DAL will beat analysts' forecast. In this case, DAL will experience a 15% increase in return. On the other hand, there is 50% chance that DAL will meet the forecast and experience a 5% increase in return. If DAL's earnings are worse than expected and the company misses analysts' estimates, the stock will experience a 12% drop. In such case, Walker estimates that the likelihood to missing analysts' estimates is 40%. Calculate the expected risk (via standard deviation) and return (via mean or expected return) for Delta Airlines given the above pay off and probability