4. Refer to the tiny sample relational database above. The purpose of a primary key field in a table is to uniquely identify the entity in that row of data. What is the purpose of a foreign key (il) field, is in the Pet table above? According to the data above or on the previous page, who owns a dog named Rover who weighs 12 pounds? If the anmal control department of a local government with the dataset above finds. Rover, what telephone number ikould they eall?.