Niagara Falls is a set of very large waterfalls located on the border between New York and Ontario, Canada. Over 200,000 cubic feet of fast-moving water falls approximately 180 feet every second. Water at the top of the Falls possesses
A.
only gravitational potential energy.
B.
neither gravitational potential energy nor kinetic energy.
C.
only kinetic energy.
D.
kinetic energy and gravitational potential energy.