Equal masses of water at 20.0°C and 40.0°C are mixed together, settling to a single intermediate temperature of 30.0°C. According to the source, what three related outcomes result from this mixing?

1. Mixing the hot and cold water has the same effect as heat transfer from the hot portion into the cold portion, and the source has already shown that this kind of transfer increases total entropy. 2. Once the two masses reach a single common temperature, no temperature difference remains, so no heat engine could be run using them anymore, meaning some energy has become unavailable to do work. 3. Before mixing, the system had two distinct temperatures with distinct distributions of molecular speeds; after mixing, there is only one uniform temperature, which the source calls a less orderly, less structured condition. 4. All three outcomes are listed together: entropy has increased, some energy has become unavailable to do work, and the system has become less orderly. 5. Option D correctly identifies the entropy increase but wrongly claims energy remains fully available, contradicting the second outcome, and options B and C reverse or deny outcomes that belong together as a coupled set, not as independent or opposite possibilities. 6. Because mixing is irreversible, all three consequences must appear together for this process; a version of events where only one or two of them occur would violate the link between entropy, work availability and disorder established earlier. _Source: OpenStax College Physics (CC BY 4.0), Ch 15 "Thermodynamics", section 15.6 Entropy and the Second Law of Thermodynamics: Disorder and the Unavailability of Energy_