Assuming that the total value is in cell A2 and percent in B2, the above formula turns into a simple =A2*B2 and returns 104.50. Remember, when you type a number followed by the percent sign (%) in Excel, the number is interpreted as a hundredth of its value. For example, 11% is actually stored as 0.11 and Excel uses this underlying value in all formulas and calculations. In other words, the formula =A2*11% is equivalent to =A2*0.11.
from my understanding, shut off pressure is the the higest pressure that can be produced by a pump and this happened at zero flow i.e. control valve closed at discharge line. so when pump running during discharge valve closed, the pressure build up in the pipe line until a maximum pressure and this maximum pressure is shut off pressure.
What does an unloader valve do? It's attached to a gas pressure washer pump and its job is to safely control/direct the flow of water into your pump. To keep your pump from being damaged. When you pull the trigger on your spray gun, the unloader valve opens wide to send your water through the pump. Then the pressurized water flows through your spray wand tip. And, when you stop spraying, it closes and it redirects the water through a hose and it is recycled through the pump again.