0.79 kg of air at pressure of 166 kPa occupies 0.41 m³ and from this condition it is compressed to 1,375 kPa accordingly to the law P*(V)^1.28 = constant. Determine change of internal energy of the air in kJ. Assume air is ideal gas.

Cp=1.005 kJ/kg K

Cv=0.718kJ/kg K

R=0.287 kJ/kg K

Write your answer up to 1 decimal point.