I'm struggling in this questions. Please help me explain, thank you so much!

1. The United States is considered a rich country because Americans can choose from an abundance of goods and services. How can there be scarcity in a land of abundance?
2. What is the difference between resource labor and resource entrepreneurship? Explain the link between labor and entrepreneurship resources and US Immigration policy.
3. Explain the link between scarcity and each of the following: (a) choice, (b) opportunity cost, (c) the need for a rationing device, (d) competition. Provide an example related to the Bay Area.