(b) A cylindrical storage tank with base area 90 m is being filled with water through an entry duct with cross-section area 250 cm, as shown in Figure 3. Concurrently, water is being extracted from the storage tank through three exit pipes to feed three different cooling systems. The inlet of the exit pipes is located 1 m above the bottom of the storage tank and the volumetric flow rate in each exit pipe is 10 L/s. Water is assumed to be inviscid and incompressible. Vin entry duct (cross-section area 250 cm) exit pipes 10 L/s 10 L/s 10 L/s 5 m 1 m storage tank (base area 90 m) Figure 3 (i) Determine the flow speed Vin required in the entry duct to maintain a constant depth of 5 m in the storage tank. marks (ii) If the depth of water in the storage tank were initially 5 m and the flow speed in the entry duct suddenly changed to Vin = 1 m/s, determine the time before water could not be extracted through the exit pipes. marks