Our environment is very sensitive to the amount of ozone in the upper atmosphere. The level of ozone normally found is 6.2 parts/million (ppm). A researcher believes that the current ozone level is not at a normal level. The mean of 23 samples is 6.4 ppm with a standard deviation of 0.7. Assume the population is normally distributed. A level of significance of 0.02 will be used. State the null and alternative hypotheses.