A researcher would like to determine whether an over-the-counter herbal nasal spray has an effect on mental alertness for infants. A sample of n = 18 infants is obtained, and each baby is given a standard dose of the spray one hour before being tested for mental alertness. For the general population of infants, scores on a mental alertness screening test are normally distributed with =60. The infants in the sample had an average score of M = 54 and an s = 8.

Can the researcher conclude that scores on the screening test are significantly different after administering the spray? Use a two-tailed test with = .05. Be sure to state your null hypothesis, a decision about that null hypothesis, and a conclusion explaining your results with an APA format statement. Calculate Cohen's d if necessary.