Weight in pounds-cats

1 9 lb two 10 lb 4 11 lb two 12 lb 1 13 lb

Weight in pounds-small dogs
1 8 lb 2 9 lb 4 10 lb 2 11 lb two 12 lb 2 13 lb 1 14 lb 1 15 lb

The dog part shows the weights of randomly selected cats and small dogs in different households what is the difference between the model weights of the cats and small dogs

0.3 lb
The model weights are the same for cats and small dogs
1 lb
3 lb

The difference between the model weights of the cats and small dogs is 3 lb.