An ideal gas changes its pressure and volume as shown in the PV-diagram starting at point A and returning to it. The pressure PAB is 2.712 atm. The volume at point B is 375.9 cm 3. How many calories are exchanged with the environment if 184.2 J of work is done on the gas during the trip B-C (see sheet 7,8) ? (Hint: The heat exchange Q asked for is for the complete "trip" A to B to C to A. What does the gas equation tell you about the temperature change, and hence about the change in internal energy, for the complete trip, when the gas returns to the same PV-pair in point A (see sheet 3,5)) ? When calculating the work you must split the complete trip into 3 pieces, WAB+ WBC + WCA.) Indicate with a positive (negative) sign whether WBC is positive (negative).