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Determine the gas production for a gas reservoir, for which the reservoir pressure has dropped from 3,000 psia to 2,300 psia. This reservoir is 1250ft in radius and 100ft in average thickness and the reservoir temperature is 120F. The porosity of the reservoir is 0.2. Also consider the following conditions: About 2/3 of the reservoir has irreducible water saturation 0.12 and the other is 0.15 . The average initial water saturation is 0.4 . When the pressure reaches to 2,300 psia, no water can be produced from this reservoir