Use Table C.2 to calculate the mass-specific enthalpy change for air undergoing a change of state from 300 K to 1000 K. How does this value compare with that estimated using the constant-pressure specific heat at the average temperature, T_avg = (300 + 1000)/2?

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TABLE C.2 Thermodynamic Properties of Air at 1 atm* T(K) h (kJ/kg) u (kJ/kg) s (kJ/kg-K) 200 325.42 268.14 3.4764 210 335.49 275.32 3.5255 220 230 240 250 260 270 280 290 300 310 320 330 340 350 360 370 380 390 400 410 420 430 440 345.55 355.62 365.68 375.73 385.79 395.85 405.91 415.97 426.04 436.11 446.18 456.26 466.34 476.43 486.53 496.64 506.75 516.88 527.02 537.17 547.33 557.51 567.70 282.49 289.67 296.85 304.02 311.20 318.38 325.56 332.74 339.93 347.12 354.31 361.51 368.72 375.94 383.16 390.39 397.63 404.89 412.15 419.42 426.71 434.01 441.33 3.5723 3.6171 3.6599 3.7009 3.7404 3.7783 3.8149 3.8502 3.8844 3.9174 3.9494 3.9804 4.0105 4.0397 4.0682 4.0959 4.1228 4.1491 4.1748 4.1999 4.2244 4.2483 4.2717 Cp (kJ/kg-K) 1.007 1.007 1.006 1.006 1.006 1.006 1.006 1.006 1.006 1.006 1.007 1.007 1.008 1.008 1.009 1.009 1.010 1.011 1.012 1.013 1.014 1.016 1.017 1.018 1.020 Cv (kJ/kg-K) 0.716 0.716 0.716 0.716 0.716 0.717 0.717 0.717 0.717 0.718 0.718 0.719 0.719 0.720 0.721 0.721 0.722 0.723 0.724 0.725 0.727 0.728 0.729 0.731 0.732 y (= Cp/Cv) 1.406 1.405 1.405 1.404 1.404 1.404 1.403 1.403 1.403 1.402 1.402 1.401 1.401 1.400 1.400 1.399 1.399 1.398 1.398 1.397 1.396 1.395 1.395 1.394 1.393