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The Urubamba River in Peru flows across a large elevation change, from about 3,500 to 2,500 meters above sea level. The surface temperature of the water varies across seasons. The river is home to fish that depend on dissolved oxygen in the water. By how much would the saturation concentration of dissolved oxygen (Coz) change from the highest point in the river to the lowest point in the river if the water's surface temperature is about 20C? Enter your answer with units of mg/L. correct to two decimal places, with a positive sign indicating an increase from the highest point to the lowest point or a negative sign indicating a decrease from the highest point to the lowest point. Tables of (1) atmospheric pressure vs. altitude and (2) Henry's Law constants at different temperatures are provided below. Hint: psia = pounds per square inch: 1 atm 14.7 psia Table 1 Altitude (meters above sea level) Atmospheric Pressure (psia) 2000 13.66 2500 13.41 3000 13.16 3500 12.92 4000 12.68 Table 2 Temperature (C) Khoz (more) Lam 10 1.7 x 10-3 15 20 1.5 x 10-5 1.4 x 10-3 1.2 x 10-3 25 You Answered -1.504 Correct Answers 0.31 (with margin: 0.01)