There are 135 people in a sport centre.77 people use the gym.62 people use the swimming pool.65 people use the track.27 people use the gym and the pool.23 people use the pool and the track.31 people use the gym and the track.4 people use all three facilities.

For a science project, a high school research team conducted a survey of local air temperatures. based on the results of the survey, the found that the average temperatures were around 10 degrees higher than expected. this result was wrong. the trouble with the survey was that most of the locations were exposed to direct sunlight and located over asphalt or sand, which resulted in higher temperatures than normal. this is a classic example of an error in which phase of inferential statistics?