Assume that 1,9 g/s of Air and 0,1 g/s of Propane (C3H8) are premixed, at Standard temperature and Pressure, and is flowing from left to right through a long tube with a diameter of 10 cm. If the mixture is ignited in the middle of the tube and the density of the Propane-Air mixture is 1,2 kg/m a. Which way does the flame propagate? b. How fast does it move? The following Laminar Flame Speed correlation may be useful: SL = 34.2-138.7(0-1.08)2, where is equivalence ratio.