「市場の失敗」、「外部性」、「福祉損失」、「配分効率」などの経済的用語の意味を説明します。上記の用語を使用して説明できるいくつかの実際の例を提供します。
Explain what is meant by economic terms like "market failure,"  "externalities,"  "welfare loss,"  and "allocative efficiency." Provide some real-life examples that can be explained using the above terms.