What is non-equilibrium steady state? And what is the difference between non-equilibrium steady state and far from equilbrium condition?

A 390-g metal container, insulated on the outside, holds 170.0 g of water in thermal equilibrium at 21.0°C. A 18.0-g ice cube, at -15.0°C, is dropped into the water, and when thermal equilibrium is reached the temperature is 12.0°C. Assume there is no heat exchange with the surroundings. The specific heat capacity of water is 4190 J/kg ∙ K, the specific heat capacity of ice is 2090  J/kg ∙ K and the heat of fusion is 3.34 × 105 J/kg. What is the specific heat capacity of the metal of the container?

What is the composition, in wt% Cr2O3, of the liquid phase in an alloy containing 71 wt% Cr2O3 at 2200C?

4. A 4 m storage tank is filled with steam and maintained at a constant temperature of 250°C. The initial pressure is 20 bar. A valve is opened and 1 kg/min of steam leaves the tank, What is the initial mass of the steam in the tank? How much time does it take for the pressure to decrease to 5 bar? [CO2]