A liquid hydrocarbon enters a 2.5-cm-diameter tube that is 5.0 m long. The liquid inlet temperature is 20°C and the tube wall temperature is 60°C. Average liquid properties are c_p = 2.0 kJ/kg · K, μ = 10 mPa · s, and ρ = 900 kg/m³. At a flow rate of 1200 kg/h, the liquid outlet temperature is measured to be 30°C. Estimate the liquid outlet temperature when the flow rate is reduced to 400 kg/h. For heat transfer in tubes, Nu ∝ Re1/3 in laminar flow and Nu ∝ Re^4/5 in turbulent flow.