The oxygen saturation level of a river is found by dividing the amount of dissolved oxygen the river water ourrently has per liter by the dissolved oxygen capacity per liter of the water and then converting to a peroent. If the river currently has 7.3 milligrams of dissolved oxygen per liter of water and the dissolved oxygen capacity is 9.8 milligrams per liter, what is the oxygen saturarion level, to the nearest percent? A. \( 34 \% \) B. \( 70 \% \) C. \( 73 \% \) D. \( 74 \% \) E. \( 98 \% \)

To find the oxygen saturation level, divide the current amount of dissolved oxygen by the capacity and then multiply by 100 to convert it into a percentage: Oxygen saturation level = (Dissolved Oxygen / Dissolved Oxygen Capacity) x 100 = (7.3 mg/L / 9.8 mg/L) x 100 ≈ 74.49% Rounding to the nearest percent gives us approximately 74%. Thus, the answer is D. \( 74 \% \). To illustrate just how important oxygen saturation is, think of fish! They need oxygen-rich water to survive, and if the level drops too low, it can lead to fish kills. This means keeping a close eye on river health is crucial for biodiversity and ecosystem balance. Lastly, if you're feeling inspired by numbers and nature, there are many fascinating studies on how oxygen levels fluctuate with temperature and human activity. You might dive into topics like eutrophication or water management strategies! They're filled with surprising data and insights about the interconnectedness of life in waterways.