Final answer:
Water boils at 212°F on the Fahrenheit scale and at 100°C on the Celsius scale, with the equivalent boiling point on the Kelvin scale being 373 K, all measured at sea level pressure.
Step-by-step explanation:
Water boils at different temperatures depending on the temperature scale being used. On the Fahrenheit scale, water boils at 212°F, and on the Celsius scale, also known as centigrade, water boils at 100°C. The Kelvin scale, which is used mainly in scientific contexts, defines the boiling point of water at 373 K. It's important to note that these boiling points are based on sea level atmospheric pressure and can change with variations in altitude or pressure.