Final answer:
Newton's 3rd law, also known as the law of action and reaction, explains why the table pushes on the book.
Step-by-step explanation:
The law that explains why the table pushes on the book when you put it on the table is Newton's 3rd law, also known as the law of action and reaction. According to this law, when an object exerts a force on another object, the second object exerts an equal and opposite force on the first object.
Learn more about Newton's 3rd law