Option: CCACC ABCCB DDAAD

Short answer: 1. According to the enterprise theory, the cost minimization function and the profit maximization function are corresponding, and the profit maximization is the cost minimization. Profit maximization means that unit output equals unit income, MC = Mr. (compare the pictures in the book.

2。 Under the condition of perfect competitive market, ① short-term equilibrium: A. When P & gtAC, the equilibrium point is E 1, the equilibrium rate of return is Q 1, and Ar 1 > According to the equilibrium condition, MR=MC. AC 1, manufacturer's profit. The profit is π = (ar-AC) * q.

B. When P=AC, the equilibrium point is E2 and the equilibrium output is Q2. According to the equilibrium conditions, MR=MC and AR2=AC2, the manufacturer is in a break-even state. Profit π=0. There is no excess profit, only normal profit.

C. when P.

(2) Long-term equilibrium: (Normal profit) Due to normal profit, the output and price of the whole industry reach equilibrium, and each manufacturer has neither loss nor excess profit, thus achieving long-term equilibrium.

Discussion: 1. Given that the elasticity of this commodity is 1.5 >: 1, we can know that this commodity is elastic. The total income of elastic goods is inversely proportional to the price change, and the price of goods must be increased to maximize the income; (The demand at the maximum income is the derivative of the demand function.

2。 ① Market failure is the inefficient or improper allocation of resources due to the failure of market mechanism to fully play its role. The main reasons are monopoly, externality, public goods and information asymmetry.

2 solution: a. Monopoly: anti-monopoly law and anti-monopoly law; B. Externality: 1) tax and subsidy policies, 2) enterprise merger (internal settlement), 3) clear property rights, and tax payment through negotiation; C public goods: (public goods are non-exclusive and non-competitive) 1) pure public goods (national defense), 2) reducing the expenditure and supply of public goods; D information asymmetry: (moral hazard and adverse selection) establish personal credit files and improve the credit system;