Consider a one-dimensional steady heat conduction process through a solid slab of thickness 0.1 m. The higher temperature side A has a surface temperature of 80 °C, and the heat transfer rate per unit area to low-temperature side B is 4.5 kW/m². The thermal conductivity of the slab is 15 W/m.K. The rate of entropy generation per unit area during the heat transfer process is ________ W/m².K (round off to 2 decimal places).

One $$kg$$ of an ideal gas (gas constant $$R=287$$ $$J/kg$$-$$K$$) undergoes an irreversible process from state- $${\rm I}$$ ( $$1$$ bar, $$300$$ $$K$$ ) to state-$$2$$ ( $$2$$ bar, $$300$$ $$K$$). The change in specific entropy $$\left( {{s_2} - {s_1}} \right)$$ of the gas (in $$J/kg$$.$$K$$) in the process is ____________

One kg of air ($${R = 287\,\,J/kg}$$-$$K$$) under goes irreversible process between equilibrium state $$1\,\,\left( {{{20}^ \circ }C,\,\,0.9\,\,{m^3}} \right)$$ and equilibrium state $$2\,\,\left( {{{20}^ \circ }C,\,\,0.6\,\,{m^3}} \right).$$ The change in entropy $${s_2} - {s_1}$$ (in $$J/kg$$-$$K$$) is _________

Two identical metal blocks $$L$$ and $$M$$ (specific heat $$=0.4$$ $$kJ/kg.K$$), each having a mass of $$5$$ $$kg,$$ are initially at $$313$$ $$K.$$ A reversible refrigerator extracts heat from block $$L$$ and rejects heat to block $$M$$ until the temperature of block $$L$$ reaches $$293$$ $$K.$$ The final temperature (in $$K$$) of block $$M$$ is ___________.