Colleen has three dogs. One year ago, Ruff weighed twice as much as Gracie and Gracie weighed 5 pounds less than Hugo. Today, all three dogs are exactly 3 pounds heavier than one year ago. Which of the following must be true today?
I. Ruff weighs twice as much as Gracie.
II. Hugo weighs more than Ruff.
III. Hugo weighs more than Gracie.