1. An experimental study was conducted by a researcher to determine if a new time slot has an effect on the performance of pupils in mathematics. Fifteen randomly selected learners participated in the study. Toward the end of the investigation, a standardized assessment was conducted. The sample mean was X = 85 and the standard deviation is 3. In the standardization of the test, the mean was 75. Based on the evidence at hand, is the new time slot effective?

Use a = 0.05