To cool boiling water quickly, you can use one of three methods:
The longest one: waiting some time: hot water cools pretty fast, so if you want warm water, this may be your best option!
The most accurate one: adding cold water. Adding a specific amount of cold water at a known temperature allows you to reach the desired temperature with little error.
The fastest one: transfer multiple times the water from one glass to another: you will be surprised by how fast it cools down!
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