how do you get 243? Thank you

An ideal gas is heated from 0.5bar,384K to 599K at a constant volume of 2.8m3. We know that for this scenario: Q=U How much heat transfer is required (in kJ )? Notice that I am asking for heat transfer in kJ and not kJ/kg or kJ/mol ! Data: R=0.23kJ/kgK,Cp=1.120.00036TkJ/kg for T in degrees Kelvin. orrect Answer 243 margin of error +/1%