Molten aluminum is degassed by gently bubbling a 75%N₂-25%Cl₂ gas through the melt. The gas passes through a graphite tube at a volumetric flow rate of 6.6x10^-5 m3 s^-1. Calculate the pressure that should be maintained at the tube entrance if the pressure over the bath is 1.014x10⁵ N m^-2 (1 atm). Data: Tube dimensions: L= 0.9 m; inside diameter = 2 mm. Temperature of aluminum melt is 973 K; density of aluminum is 2500 kg m-3. Dynamic Viscosity of the mix at 973K is 2.665E-5 Pa-s