Final answer:
Water is the essential natural resource equally necessary for both economically developed and developing nations for daily living, industrial, and agricultural purposes. It's a critical element for sustainable global development, requiring prudent conservation and management.
Step-by-step explanation:
The natural resource that is needed as much in economically developing nations as it is in countries that are already economically developed is water. This vital resource is crucial for daily living, industry, and agriculture. Rich nations have the ability to build infrastructure like deep wells and large dams to supply their populations with water, leading to high usage rates. On the other hand, poorer nations often struggle with developing such water supplies due to financial constraints. As global population grows, especially in developing countries, the demand for this essential resource only increases, making water conservation and management a critical issue for sustainable development.