Washington State law says dissolved oxygen in marine waters must not be less than 5 m/L. The Washington
Department of Ecology uses their Salish Sea model to predict the concentration of dissolved oxygen in the Puget Sounds at any given place and time to see where dissolved oxygen is below the 5 mg/L threshold. Their reported standard deviation around this prediction is 1 mg/L. What value of dissolved oxygen must their model predict in order to be 95% confident that the true value is in fact below the threshold? Repeat for 80% confidence. What are you assumptions?