Here are the answers to your questions:
Question 1: Which of the following challenges affect economic growth in Africa?
Response: All of the above
Question 2: How does a country's literacy rate affect its standard of living?
Response: The higher the literacy rate a country has, the higher the standard of living for its people.
Question 3: How does improving infrastructure with projects like construction help a country's economy?
Response: Improving infrastructure enables a country's workforce to optimize their productivity and contribute more to the economy.
Question 4: Which three countries boast petroleum as its top export?
Response: Libya, South Sudan, Congo
Feel free to ask if you have more questions!