A factory recently installed new pollution control equipment ("scrubbers") on its smokestacks in hopes of reducing air pollution levels at a nearby national park. Past sampling in the park has shown a mean sulfate level of 8.3 with a standard deviation of 1.8) After the installation of the scrubbers a set of 10 randomly timed measurements of sulfate levels (in micrograms per cubic meter) were taken with a sample mean of 5 and a standard deviation of 2.84) We believe that measurements of sulfate levels are normally distributed. Do these data provide sufficient evidence at the 0.01 level of significance to conclude that the scrubbers have reduced sulfate levels in the park? Evaluate assumptions, state your null and alternative hypotheses and run the appropriate test.