Although an enterprise's internal trade fair eliminates or reduces some of the market transaction costs, it also brings with it the specific transaction costs of the enterprise. The main reason for this defect is also the incompleteness of information. Specifically, first, there are various contractual relationships among enterprises, including contractual relationship between enterprises and workers, contractual relationship between enterprises and managers, etc. The enterprise should supervise the work of the workers and products that it employs, as well as the managers and other personnel, and induces them to work hard for the enterprise. So, companies are signing contracts and spending on oversight and incentives. Secondly, on the one hand, corporate decision makers often need to obtain information from subordinates. On the other hand, the decision-making information of the upper level of the enterprise should be realized by passing it to the subordinate. The information transmission of these two different directions will be distorted by the increase of subordination of enterprise scale, resulting in the loss of enterprise efficiency. Once again, the subordinate of the enterprise often conceals or passes the wrong information to the superior for selfish motives, so that the superior can make decisions that benefit the subordinate. Or, the subordinate's decision to the superior only passes or executes the part that is advantageous to oneself. These will result in the loss of enterprise efficiency. Thus, the expansion of enterprises is limited. According to coase's theory, the scale of the enterprise should be expanded to this point, that is at this point to increase the cost of an internal exchange cost equals the cost through the market exchange cost and so on. As the dental industry is rapidly expanding, the requirement of dentists and staffs has risen tremendously. A dental clinic needs to consider employing more and more candidates to own top quality and efficient patient care. Apart from patient care, there are lots of other needs that have to be handled with professionalism, trust , care. It is because of this belief that some of the most efficient and experienced staffs including dentists are expected in the industry. However, occasionally, the need for extra dentists could be short-term. On the other hand, some dental practices may additionally require a temporary dentist to meet the duties of another. Xpoint fills the cost and cost gap between high speed and high cost DRAM and low cost NAND. Does this technology engulf DRAM and NAND markets? Customers who purchase a large number of Xpoint chip/drives may purchase fewer DRAM chips and NAND chips/drives. But trump and republicans seem willing to take the risk. After all, by pushing the middle class to raise interest rates, they have already laid out plans for the 2018 and 2020 elections. From now on, they can boast about most family tax cuts. They are expected to peak in the run-up to the presidential election in 2019 and before the bill expires. (3) lorries: vehicles mainly used for transporting goods.