If the percentage of fuel in a fuel-air mixture falls below a certain value called the lower flammability limit (LFL), which is sometimes referred to as the lower explosion limit (LEL), the mixture cannot be ignited. In addition there is an upper flammbility limit (UFL), which is also known as upper explosion limit (UEL). For example, the LFL of propane in air is 2.3 mole % C3H8 and the UFL is 9.5 %.If the percentage of propane in a propane-air mixture is greater than 2.3 % and less than 9.5 %, the gas mixture can ignite if it exposed to a flame or spark. A mixture of propane in air containing 4.03 mole % C3H8 (fuel gas) is the feed to a coombustion furnace. If there is a problem in the furnace, a stream of pure air (dilution air) is added to the fuel mixture prior to the furnace inlet to make sure that ignition is not possible. a) Draw and label a flowchart of the fuel gas-dilution air mixing unit, presuming that the gas entering the furnace contains propane at the LFL, and do the degree of freedom analysis. b) If porpane flows at a rate of 150 mol C3H8/s in the original fuel-air mixture, what is the minimum molar flow rate of the dilution air?c) How would the actual dilution air feed probably compare with the value calculated in Part (b)? (<,>,=) Explain.