A thin wall capillary is filled with pure gas at an absolute pressure of 5 atm. The gas penetrates the wall of the capillary and it is rapidly diluted in the ambient medium which is essentially free of this gas. How long is required for 90 % of the gas to leak from the capillary? Data R=625 m. Inside diameter= 1250m. Wall thickness= 20m. T=27C R= 8.314 Joule/K mol Permeability coeff: P=10^-15 mol/m.s.Pa