3. A large internal-combustion engine takes in 2kg/s of air and 8.81/min of fuel, relative density of 0.85. The exhaust pipe has a diameter of 400mm and the exhaust gas has a density of 0.4kg/m³. Assuming steady flow conditions, calculate the velocity of the exhaust gas. (42.3 m/s) 4. Steam with specific volume 1.6m³/kg flows in a pipe of diameter 250mm with velocity 20m/s. Further downstream the pipe reduces to 200mm, where the specific volume of the stream increases to 1.9m³/kg. Determine: a. Upstream volume flow rate and mass flow rate. b. Downstream velocity, volume flow rate and mass flow rate. (a. 0.982m³/s, 0.614kg/s b. 37.1m/s, 1.17m³/s, 0.614kg/s) 5. A coal-fired steam generator under steady flow conditions uses 1.8 T/h of coal, of ash content 5%. The air-fuel ratio (by mass) is 18:1. The exhaust gas enters a stack of diameter 1.8 m at which point the gas has a specific volume of 3.6m³/kg. Calculate: a. Volume flow rate and mass flow rate of exhaust gas. b. Velocity of gas entering the stack. (a. 34.11 m³/s, 9.475 kg/s b. 13.4 m/s)