Question: Obstacle Course Times. An obstacle course was set up on a campus, and 10 volunteers were given a chance to complete it while they were being timed. They then sampled a new energy drink and were given the opportunity to run the course again. The before and after times in seconds are shown below. Is there sufficient evidence at a = 0.05 to conclude that the students did better the second time? Discuss possible reasons for your results.

Student 1 2 3 4 5 6 7 8

Before 67 72 80 70 78 82 69 75

After 68 70 76 65 75 78 65 68