Which one of the graphs below best illustrates the relationship between internal energy U of an ideal gas and temperature T of the gas in K?

A refrigerator with coefficient of performance 0.25 releases 250 J of heat to a hot reservoir. The work done on the working substance is

A vessel has 6 g of oxygen at pressure p and temperature 400 K. A small hole is made in it, so that oxygen leaks out. How much oxygen leaks out if the final pressure is p/2 and temperature is 300 K?

In a steady state, the temperature at the end $$A$$ and end $$B$$ of a $$20 \mathrm{~cm}$$ long rod $$A B$$ are $$100 \Upsilon$$ and $$0^{\circ} \mathrm{C}$$. The temperature of a point $$9 \mathrm{~cm}$$ from $$A$$ is