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Purpose The purpose of my project is to determine if there is any significant difference in dissolved oxygen (DO) levels as measured by the traditional HACH® method or the newly developed CHEMets® test kit under typical field conditions. Hypothesis My hypoth ....

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.... large investments in point-source pollution control have yielded no statistically significant pattern of improvement in dissolved oxygen levels in water in the last 15 years. It may be that we are only keeping up with the amount of pollution we are producing. (Knopman, 1993) The early biosphere was not pleasant for life because the atmosphere had low levels of oxygen. Photosynthetic bacteria consumed carbon dioxide and produced simple sugars and oxygen which created the oxygen abundant atmosphere in which more advanced life forms could develop. (Brown, 1994) The mystery of how Earth's oxygen levels rose is very complex. Scientists don't agre ....