State the Clausius inequality in words. An inventor claims that he has developed a heat engine which absorbs 1200 kJ and 800 kJ from reservoirs at 800 K and 600 K respectively and rejects 600 kJ and 200 kJ as heat to reservoirs at 400 K and 300 K respectively. It delivers 1200 kJ work. Determine whether the heat engine is theoretically possible.