A Shaman is attacking a dragon. The Shaman's normal attack does 250 damage. There is a 15% chance of getting a critical strike for 500 damage, and a 20% chance of getting a Windfury attack for 800 damage. There is also a 10% chance that his attack will miss, causing 0 damage. Let the random variable X represent the damage his attack does. Sketch a table showing the different possible values of X, and the probability of each. What is the standard deviation of the Shaman's attack damage? (Round your answer to two decimal places)