The Brayton cycle shown in Figure P16.61 is the idealized cycle for a gas turbine or jet engine. Consider an engine using the Brayton cycle that operates on 0.070 mol of ideal gas between the pressures P_i = P₁ = P₂ = 4.9 atm and P_f = P₃ = P₄ = 3.5 atm with volumes V₁ = 0.50 L, V₂ = 1.00 L, V₃ = 1.22 L, and V₄ = 0.61 L. Retain three significant figures in all calculations. 

(a) Determine the work done for the displacements 1→ 2 and 3 → 4. 

(b) Determine the temperature of the ideal gas at each point. 

(c) Calculate the work done for the adiabatic expansion 2 → 3 and contraction 4 → 1. Consider the change in internal energy. 

(d) What is the total work done by one cycle? 

(e) Determine the amount of heat flowing in, Q_H - Q₁ → 2 during the isobaric expansion and the heat flowing out of the gas during the isobaric contraction, Q_C → Q₃ → 4. The specific heat per mole for an ideal gas under constant pressure is given by C_P = C_V + R. 

(f) Determine the efficiency for this Brayton engine (Eq. 16.18). The heat loss and friction in a real Brayton engine will reduce this ideal efficiency. (e) Calculate and compare to the efficiency of a Carnot engine running between the same high and low temperatures.

Figure P16.61