Final answer:
The boiling point of water at an atmospheric pressure of 81 kPa is slightly below 100°C.
Step-by-step explanation:
The boiling point of water is affected by atmospheric pressure. At higher altitudes, where the atmospheric pressure is lower, water boils at a lower temperature. The boiling point of water at sea level, where the atmospheric pressure is standard, is 100°C. However, at an atmospheric pressure of 81 kPa, the boiling point of water would be slightly lower than 100°C.