Our environment is very sensitive to the amount of ozone in the upper atmosphere. The level of ozone normally found is 3.8 parts/million (ppm). A researcher believes that the current ozone level is at an excess level. The mean of 9 samples is 5.9 ppm with a standard deviation of 1.2. Does the data support the claim at the 0.025 level? Assume the population distribution is approximately normal. Step 2 of 5: Find the value of the test statistic. Round your answer to three decimal places