Here are the answers to your questions:
Question 24: What is the term for an artificially defined informal geographic area with similar cultural, economic, or environmental characteristics?
Answer: a region
Question 25: Which of the following best explains an important limitation of per capita national income?
Answer: Wealth distribution in most countries is uneven
Question 26: What conclusion can you draw about the level of economic development in a country in which most workers are in the tertiary and quaternary sectors of the economy?
Answer: Countries in which most workers are in these sectors typically have a high level of economic development.
Question 27: Which of these features helps you recognize that an organization is a supranational organization?
Answer: The organization is made up of many individual countries.
Feel free to ask if you need further clarification or help!