question: An ideal gas initially at 230 K undergoes an isobaric expansion at 3.65 kPa. If the volume increases from 1.7 m^3 to 6.8 m^3 and 25.1 kJ is transferred to the gas by heat, what is the change in its internal energy? i know that isobaric expansion means that the pressure is constant. however, i dont know how to calculate the internal energy. my proff went over this part very briefly and the book doesnt cover much about this topic.