Figure 19-26 shows two paths that may be taken by a gas from an initial point i to a final point f. Path 1 consists of an isothermal expansion (work is 60 J in magnitude), an adiabatic expansion (work is 38 J in magnitude), an isothermal compression (work is 47 J in magnitude), and then an adiabatic compression (work is 14 J in magnitude). What is the change in the internal energy of the gas if the gas goes from point i to point f along path 2?