Please answer the questions

In the united states, one worker can produce 10 tons of steel per day or 20 tons of chemicals per day. in the united kingdom, one worker can produce 5 tons of steel per day or 15 tons of chemicals per day. the united kingdom has a comparative advantage in the production of:

Adecision is made at the margin when each alternative considers

Which of the following is the term for something that you can't live without 1. need 2. want 3. good 4. service