Please show all steps and try to always begin every problem with the system balance equation (for example: Ein - Eout = ?U). The necessary tables are included in the links below...

6) 2 kg of Oxygen is heated from 309C to 130C. Determine the amount of heat needed if this is done at {a} constant volume and (b) constant pressure. Solve this problem using thermodynamic tables, as well as by using average specific heat, and compare your answers