As shown in Fig. P8.87, a standard household water meter is incorporated into a lawn irrigation system to measure the volume of water applied to the lawn. Note that these meters measure volume, not volume flowrate. (See Video V8.16.) With an upstream pressure of p1 = 50 psi the meter registered that 120 ft3 of water was delivered to the lawn during an "on" cycle. Estimate the upstream pressure, p1, needed if it is desired to have 150 ft3 delivered during an "on" cycle. List any assumptions needed to arrive at your answer.
