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(4) Profit-seeking intermediaries widely exist in product, labor, financial and other markets. These intermediaries charge fees, resulting in higher product prices for consumers, lower compensations for workers and lower returns for depositors/investors. Why do consumers, workers and investors still need these intermediaries in the market economy, especially in a more developed market economy? (10%; your answer to this question should not exceed one page) (5) Economics (including finance) is a social science that studies how to allocate scarce resources. Neoclassical economics is a school of economics that has dominated the economic thought since the 20th century. All the economic and financial theories you have learned so far belong to neoclassical economics. These theories are based on several fundamental assumptions of human behavior. Can you list at least four of these assumptions and briefly explain them? (10 % , your answer to this question should not exceed one page)