A dog food company wants to compare a new lower-calorie food with their standard dog food and their 'Mature Dog Food' to see if it’s effective in helping inactive dogs maintain a healthy weight. They have found several dog owners willing to participate in the trial. The dogs have been divided into groups based on their size: small, medium, or large breeds, and the company will randomly supply owners of each size dog with one of the three foods (new, standard, adult dog food).
The owners have agreed not to feed their dogs anything else for a period of 6 months, after which the dogs’ weights will be checked.
How many levels of the factor(s) are in this experiment?
Remember, the factor is the thing(s) being evaluated or manipulated in the experiment.