in this study "An experiment was designed by a team of Sport Psychologists to investigate the effects of positive and negative imagery on golf putting performance. Twelve golfers participated in the experiment over a three-day period. On one day they performed 100 putts in a control condition (no imagery), on another they performed 100 putts in a negative imagery condition, and on a different day they performed 100 putts in a positive imagery condition. All golfers completed the control condition on Day one, but the order of the negative/positive imagery was counterbalanced",How many groups/ conditions are there? How many independent variables are there and how many/ which levels? Are participants tested once or multiple times