Textbook Problem

(Indicates a review question, which means it requires only a basic understanding of the material to answer. Questions without this designation typically require integrating or extending the concepts presented thus far.)

A person places a hand on a closed book resting on a table and then presses downward while pushing forward. Either the book slides across the table or the hand slides across the hook. What determines which event happens? Which type (s) of friction is (are) involved?