When 3.0 mol of O₂ (g) is heated at a constant pressure of 3.25 atm, its temperature increases from 260 K to 285 K. Given that the molar heat capacity of O₂ at constant pressure is 29.4 J/K-mol, calculate q, ∆H, ∆U. Ans: 2.2 kJ, 2.2 kK, 1.6 kJ