To double-check the information provided in question 21, you can follow these steps:
1. Read the question thoroughly to understand what is being asked.
2. Identify the topic of the question, which in this case is the seven inputs common to all technological systems.
3. Find reliable sources of information such as textbooks, academic journals, or reputable websites.
4. Search for information related to the seven inputs common to technological systems, which are people, materials, tools (machines), energy, information, finances, and time.
5. Cross-reference the information found in different sources to ensure accuracy and consistency.
6. Compile the information and verify that each input is properly defined and explained with examples.
7. Compare the compiled information with the answer provided above to see if any discrepancies exist.
By following these steps and conducting thorough research, you can double-check the provided information and ensure its accuracy.