3. Natural gas is transported in a 100-m-long, 1-cm-thick, 3-m-internal-diameter steel tube at a pressure of 500 kPa and 293 K. Determine the highest rate of hydrogen loss, in kg /s, through this tube if the partial pressure of hydrogen in natural gas is 8%. Consider that the solubility of hydrogen in steel, in terms of its mass fraction, is given by WH2=2.09x10-4exp(-3950/T) PH,0-5, where PH2 is the H2 partial pressure of in bar and T is the temperature in K. Consider further that the diffusivity of hydrogen in steel is 2.9x10-13 m/s and that the system is in steady state