Nitrogen flows at steady state through a horizontal, insulated pipe with inside diameter of 38.1mm. A pressure drop results fro flow through partially opened valve. Just upstream from the falve the pressure is 690kPa, the temperature is 322.15K, and the average velocity is 6.09ms^(-1). If the pressure just downstream from the valve is 138 kPa, what is the temperature? Assume for nitrogen that P V / T is constant, CV = (5/2) R, and CP = (7/2) R.

Correct answer: T2/t2=320.57 k/47.42°C

Please explain steps. Name each equation youre using