Answer to Question 1
The unattainable combinations of production that lie beyond the PPF illustrate the concept of scarcity. There simply are not enough resources to produce any of these combinations of outputs. Additionally, while moving along the PPF to increase the production of one good requires that the production of another good be reduced, which also illustrates scarcity.
Answer to Question 2
a. Opportunity cost is the best alternative use of a resource. The opportunity cost of a particular choice is measured in terms of the benefit foregone from the next best alternative. To facilitate comparison, the benefits and costs of various choices are translated into monetary units like dollars.
b. The opportunity cost of backpacking across Europe, for a particular person, is the cost of anything else that could have been done in that year. The backpacker could have attended college or started working. These costs are the opportunity costs of the gap year. This, however, does not mean that backpackers are irrational, because the benefits may exceed the cost. Every action has an opportunity cost. The choices that people make are optimal based on their perceived costs and benefits.
projections of future oil production
Abiotic production of biomolecules
What are examples of ideal forms?
Human of the planet's net primary production and appropriation of NPP
Modern Predication of Peak in Global Oil Production
Production efficiency vs. trophic efficiency