what is the steps to get the answer shown?

Use the following data for solving problems: Viscosity of methane ()=0.011103kgm1s1 Molecular weight (M)=16.0kgkmol1 Universal gas constant (R)=8314Jkmol1K1 1. 50kgs1 of a natural gas (essentially methane) is required to flow through a 0.6 m diameter and 4km long pipeline (relative roughness =0.0014 ) at a constant temperature of 20C, and to discharge at a pressure of 5atm. What upstream pressure will be required to maintain the flow rate? [Ans. 9.32atm]