Firefighters use a hose with a 2-cm exit nozzle connected to a hydrant with an 8-cm-diameter opening to attack a fire on the second floor of a building 6 m above the hydrant, as shown in the figure.

What pressure must be supplied at the hydrant to produce an exit velocity of 15 m/s? (Assume the density of water is 1,000 kg/m3, and the exit pressure is 1 × 105 Pa.)