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A 2km long coated steel pipeline is connected horizontally at the bottom of a 1.4m diameter Jojo tank filled with rainwater and fully open to the atmosphere as shown in Figure 2. The exit point of the coated steel pipeline, friction factor f=0.02, is 10m from the top level of the rainwater inside the tank. In order to recover the rainwater inside the Jojo tank, the valve placed at the exit point of the coated steel pipeline is fully open so 2 TPH3701 Assessment 2/2023 that the velocity reaches 80% its final value. Calculate the time it will take to recover the rainwater. Figure 2: Schematic illustration of a Jojo tank