Golf ball manufacturers are constantly looking for ways to improve the performance of their products. One producer came up with an idea to help high handicap golfers (i.e., they’re not very good), who typically slice the ball. (For a right-handed golfer, a slice is a ball that curves to the right.) The manufacturer produced three prototypes that are designed to go straighter than conventional balls. An experiment was conducted wherein 20 high handicap golfers who slice the ball were recruited and asked to use their drivers to hit one shot with each type of ball. The distance from the green was measured. 

a. Is there sufficient evidence to infer that there are differences between the three prototypes?

b. What do the data tell you about the way the experiment was conducted?