Solve the Problem Let a = the Set of Dogs Who Have Demonstrated

Solve the problem.
-The Little Town Dog Club offers a "Puppy Kindergarten" for puppies in their community. In order for a dog to
advance from this introductory class to the first level obedience class, it must consistently demonstrate
knowledge of each of 4 commands. The instructor has the following table in her record book. $$\begin{array} { l | c c c c } & \text { Sit/Stay } & \text { Down/Stay } & \text { Heel } & \text { Come } \\\hline \text { Amber } & \text { Yes } & \text { Yes } & \text { No } & \text { Yes } \\\text { Bruiser } & \text { No } & \text { Yes } & \text { No } & \text { Yes } \\\text { Keaton } & \text { Yes } & \text { Yes } & \text { Yes } & \text { Yes } \\\text { Ollie } & \text { No } & \text { No } & \text { No } & \text { Yes } \\\text { Rolf } & \text { Yes } & \text { No } & \text { Yes } & \text { Yes }\end{array}$$ Let A = the set of dogs who have demonstrated knowledge of Sit/Stay.
Let B = the set of dogs who have demonstrated knowledge of Down/Stay.
Let C = the set of dogs who have demonstrated knowledge of Heel.
Let D = the set of dogs who have demonstrated knowledge of Come.
Give each of the sets A, B, C, and D using roster notation. Determine the set A ∩ B ∩ C ∩ D. Which dogs are ready to
advance to the next level?