The says that, as we take more and more observations at random from any population, the distribution of the mean of these observations eventually gets close to a normal distribution.

In a study, people were asked to imagine simple occasions that made them happy and to remember events that made them feel proud about themselves. it was observed that the subjects developed an increasingly positive attitude. these changes are known to be healthy, leading to greater physical activity and reducing unhealthy habits. based on this excerpt, we can conclude that a positive attitude .