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Air flows at steady state through a horizontal, insulated pipe with inside diameter of 4 cm. A pressure drop results from flow through a partially opened valve. Just upstream from the valve, the pressure is 7 bar, the temperature is 43C, and the average velocity is 20 m.s? If the pressure just downstream from the valve is 1.3 bar, what is the temperature? Assume for air that PVI T is constant, Cu= (5/2)R, and Cpr (7/2)R. (Values for R, the ideal gas constant, are given below.) The average molecular weight of air is 0.02897 kg.mol-1. Values of the Universal Gas Constant R 1 = 8.314 J-mol-1.K-1 = 8.314 m Pa.mol-1 K-1 83.14 cm.bar.mol-?.K-1 = 8314 cm' kPa.mol-?.K-1 = 82.06 cm (atm).mol-? K-? = 62, 356 cm:(torr).mol-?K- 1.987 (cal).mol-?-K-? = 1.986 (Btu)(lb mole)- (R)-1 0.7302 (ft)' (atm) (lb mol)--(R)-- = 10.73 (ft)' (psia) (lb mol)--(R)-1 1545 (ft) (lbf) (lb mol)(R)-1 -1 -1 = The temperature is C