What happens to the potential energy of a book that is dropped from a desk to the floor? A.
It gains mass.

B.
It stays the same.

C. It increases as the book falls.

D.
It is converted into kinetic energy.

D.   It is converted into kinetic energy.

Explanation:

When a book is dropped from a desk to the floor, the potential energy of the book is converted to kinetic energy as it falls.

"hydrogen bonding is the attraction of h atoms in the water molecule (slight + charge) to o atoms in a neighboring water molecule (slight - charge); it is a weak interatomic force. but it is still strong enough to the water molecules "stick" together."