The paper integrates microeconomic and macroeconomic principles, emphasizing policy analysis and real-world applications. Section A explores marginal productivity, externalities, opportunity cost, and financial stability, with topics like market failures, labor dynamics, and fiscal policies. The focus is on resource allocation, cost-benefit analysis, and policy trade-offs. Section B investigates climate change economics, highlighting greenhouse gas emissions, government intervention, and sustainable development. Key themes include public goods, asymmetric information, and innovation′s role in economic growth. The paper emphasizes analytical skills, evaluating the implications of economic decisions on markets, labor, and environmental policy.