A person moves a book from a 30-cm high coffee table to the top shelf of a bookshelf approximately 2.5 m high. Which statement correctly describes the gravitational potential energy of the book?

Gravitational potential energy increases with height above a reference point: GPE = mgh. The shelf is about 2.5 m high, while the table is only 0.30 m high, so the book has more gravitational potential energy on the shelf. Its energy is not constant regardless of position.

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