In the long term equilibrium production of perfectly competitive firms, there must be 20

Pick D. You put all the pictures together, the short-term long-term average of the marginal cost.

These four curves all converge or cut at the lowest point of the LAC, at which point the average cost of production falls to the lowest point of the long-term average cost, and the commodity** is equal to the lowest long-term average cost. I got option d. At this point, the profit of a single manufacturer is zero.

1.Short-term equilibrium.

at fixed costs.

That is, during the period when the scale of production remains unchanged, the manufacturer cannot adjust the scale of production, but can only change the output by increasing or decreasing the amount of its variable inputs, so as to maximize profits or minimize losses. When each manufacturer reaches its own profit maximization state, it achieves a short-term equilibrium, and thus the entire industry also reaches an equilibrium state.

2. Long-term equilibrium.

in a perfectly competitive market.

** Under given conditions, the manufacturer has a long-term production of all factors of production.

The adjustment can be manifested in two aspects, on the one hand, in the choice of the optimal production scale, and on the other hand, in the decision to enter or exit an industry. In the long run, the adjustment of the above two aspects is carried out at the same time, and in the long-term equilibrium state, the excess profit of the manufacturer.

Zero. Extended Resources:

1. What does it mean to lose fiber in a perfectly competitive market?

A perfectly competitive market is also known as a purely competitive market.

or free competition market, refers to a market in which there are a large number of production and sales enterprises in an industry, and they all provide the market with the same and standardized products (such as grain, cotton and other agricultural products) in the same way. Neither the seller nor the buyer has control over the goods or services. In this competitive environment, since both buyers and sellers have no influence on the company, they can only be the recipients of the company, and any price increase or price reduction behavior of the enterprise will cause a sharp decrease in the demand for the company's products or unnecessary loss of profits.

Therefore, the product** can only be determined by supply and demand.

2. Conditional characteristics.

There are a large number of buyers and sellers.

Because of the large number of producers and consumers, the proportion of empty rubber rented by any one producer and the purchase by any one consumer is very small compared to the production (sales) and purchases of the market as a whole. As a result, no producer or consumer has the ability to influence the market's output and**. Any individual market behavior of producers and consumers does not cause changes in market output (i.e., sales volume) and**.

In another way, it is the elasticity of supply faced by any buyer.

is infinity, and so is the elasticity of demand faced by sellers.

Product homogeneity.

There are many enterprises in the market, each enterprise is not only a homogeneous product in the production of a certain product, but also no difference in the quality, performance, shape, packaging and so on of the product, so that any enterprise can not influence the monopoly through its own products with the specificity of other people's products, so as to enjoy the monopoly benefits. For consumers, no matter which company's products are purchased, they are homogeneous and undifferentiated products, so that many consumers cannot form preferences according to the differences in products, and buyers do not care about manufacturers and brands when buying goods in the market. That is to say, when various commodities are completely substitutable to each other, it is easy to approach a perfectly competitive market.

In the perfectly competitive market in Luzhong, the conditions for the short-term equilibrium of manufacturers are:

The marginal cost (MC) is equal to the marginal benefit (MR), that is, the manufacturer will produce until MC=MR.

Market**(p) equals average cost (ac). Because in a perfectly competitive market, the firm does not have the ability to control the market ** and can only accept the market**, so the producer can only make a trade-off between AC and the market**, i.e., p=ac

The manufacturer's output is adjustable. That is, the bridge manufacturer can adjust the output under limited conditions.

No or very little inventory. That is, the manufacturer does not have a reserve inventory in the short term or the inventory is very small.

These conditions are the basis for the short-term equilibrium of the firm in a perfectly competitive market.

The formation and nature of the long-term equilibrium of perfectly competitive firms: Equilibrium refers to an equilibrium achieved by firms in the long run by changing the input quantities of all factors to achieve the purpose of maximizing profits.

The supply and demand of the market determine the equilibrium of the market and the equilibrium output, and the manufacturers adjust the scale of plant equipment according to the equilibrium of the market.

At the same time, there are new manufacturers entering and loss-making manufacturers exiting the industry, when the supply and demand of the product are at a certain level, and P0 reaches equilibrium.

If this level is equal to the lowest long-term average cost of the manufacturer, then the number of processors**, production volumes, and the number of surviving manufacturers for that product will no longer change, because each manufacturer will not have excess profits (and thus no more production will be expanded, and no new manufacturers will be added).