Microeconomics focuses on the behavior of individual agents (consumers, firms) and price determination in specific markets. Macroeconomics analyzes the economy-wide phenomena such as total output (GDP), unemployment, and inflation.

Opportunity cost is a fundamental concept representing the benefits an individual, investor, or business misses out on when choosing one alternative over another.

In Monopolistic Competition (e.g., toothpaste, soaps), many sellers offer differentiated products. This differentiation allows them to act as price makers to a limited extent, unlike Perfect Competition where products are identical.

Points on the PPF curve represent full efficiency. Points outside are unattainable with current resources. Points inside indicate that resources are idle or inefficiently used.

While total utility may increase, the *additional* satisfaction gained from consuming each subsequent unit declines. This explains the downward sloping demand curve.

As you produce more of Good A, you have to give up increasingly larger amounts of Good B because resources are not perfectly adaptable. This increasing trade-off creates the concave shape.

The law states that as you add more variable inputs (labor) to a fixed input (land), marginal product will eventually decline. This distinction of fixed vs variable inputs defines the Short Run.

Internal economies are cost advantages that a specific firm reaps as it grows larger (e.g., purchasing bulk raw materials cheaper, specialized machinery). External economies benefit the whole industry.

Public Goods (like national defense, street lights) are non-excludable (you can't stop people from using it) and non-rivalrous (one person's use doesn't reduce availability for others).

Positive economics relies on facts and data (descriptive). Normative economics involves value judgments and opinions about economic fairness and goals (prescriptive). Both definitions are correct.

A decrease in supply shifts the supply curve to the left. With constant demand, this creates a shortage at the old price, pushing the equilibrium price up and quantity down.

Land is considered a primary factor of production with a fixed supply. Unlike capital or labor, which can be increased or decreased based on demand and investment, the total physical availability of land is geographically limited and cannot be significantly expanded, making its supply curve perfectly vertical (inelastic).

Normative economics expresses values, judgments, or opinions about what "should" or "ought" to happen. It involves subjective statements that cannot be proven true or false. The other options are Positive Economics, which state factual or testable relationships.

The Production Function (Q = f(K, L...)) mathematically shows the maximum amount of output that can be produced from a given set of physical inputs (like capital and labor), assuming a certain level of technology.

"For whom to produce" is about distribution. It determines who gets to consume the goods produced, which depends on how income is distributed (wages, rent, interest, profit) among the factors of production.