The equation below can be used to find the specific heat capacity of a substance. What is the specific heat capacity if it takes 1000 J of energy to heat 25 g of this substance by 100°C? Give your answer in J/kg°C.

Two kilograms of air within a piston–cylinder assembly executes a carnot power cycle with maximum and minimum temperatures of 800 k and 300 k, respectively. the heat transfer to the air during the isothermal expansion is 60 kj. at the end of the isothermal expansion the volume is 0.4 m3. assume the ideal gas model for the air. determine the thermal efficiency, the volume at the beginning of the isothermal expansion, in m3, and the work during the adiabatic expansion, in kj.