In a High School Science Laboratory, students were able to find out that the faecal coliform count in the nearby river exceeds the desirable limit of 500 mpn per 100 ml of sample. To address this problem, the students designed an experiment using bioremediation technique to significantly decrease the faecal coliform count in the river. The mean Faecal Coliform Count is 465.90 with a Standard Deviation of 85.4744. At .05 level of significance, test the hypothesis that the bioremediation technique significantly decreased the faecal coliform count in the water samples. Assume the populations to be approximately normal. (T-Test)