Final answer:
The author's purpose is to inform readers about how to properly hard-boil eggs, which is influenced by understanding the boil point of water in relation to atmospheric pressure and its impact on cooking time.
Step-by-step explanation:
The author's purpose in the text suggesting how to boil eggs is to inform the reader about the correct method for cooking hard-boiled eggs. The process of cooking an egg involves understanding the properties of water and its boiling point under various atmospheric pressures which affect how quickly eggs cook. In places with higher elevation such as Denver, the boiling point of water is lower due to lower atmospheric pressure, which means water boils at a lower temperature compared to at sea level in New York City. Therefore, in Denver, it takes a longer time for an egg to cook because the temperature of the boiling water is not as high as it would be at sea level, and hence the reaction rate of cooking the egg is slower.
The principles described here involve several concepts, including the relationship between pressure and boiling point, and that temperatures above 373 K (100°C or 212°F) are necessary for the albumin protein in egg whites to denature and solidify, a process that is spontaneous and irreversible at these temperatures. Variables such as the temperature of the water when it starts boiling and the external atmospheric pressure affect the cooking time and efficiency. For instance, at high altitudes, where pressure is lower, a pressure cooker might be used to increase the pressure and thus the boiling point of water to cook food faster.