How do firms choose their overhead cost assignment? How do firms choose optimal cash strategy determined by critical production activities that create and capture values? What is the nature and function of expense assignment? What are reasons for expense indicators or cost drivers? What are some policy implications of the Activity Based Costing in formulating effective cost assignment and spending budget strategies? Michael Zezas, an analyst at Morgan Stanley, also said the tax legislation would be a boon to the market in the short term, but may not be able to make fundamental changes. The current flattening of the us Treasury yield curve shows that the medium-term slowdown in the us economy and the recession of 2019 are not going away. A tax reform would widen the fiscal deficit, possibly in the future and exacerbate cyclical risks in the economy. Any transaction can be seen as a contract between the two parties. The so-called transaction cost can be seen as the cost of the transaction contract. According to Mr Coase and others, a type of transaction costs arise from the accidental factors that occur when a deal is signed. These incidental factors may not be written into the contract due to the fact that they could not be foreseen in advance, or although they could be foreseen, they could not be written into the contract due to too many factors. Another type of transaction costs is the signing of contracts and the cost of monitoring and enforcing contracts. The correlation between optimal spending budget and effective activity-based costing is very important to sound business strategic options designed to maximize the wealth producing capacity from the enterprise. In these series on effective cost assignment and optimal cash strategy, we're going to focus on the pertinent strategic cost questions and proffer some operational guidance. Economic profits in perfect competition and monopolistic competition market has a special purpose, a positive profit can attract more enterprises to enter the market, increasing competition and push the market equilibrium price low, exclude some enterprises lack of competitiveness in the market, to achieve long-term equilibrium; On the contrary, negative economic profit can eliminate some of the original enterprises in the market, because the supply is reduced, the market equilibrium price will be pushed up, and the long-term equilibrium will be achieved. The result of the two cases is that economic profits disappear from each manufacturer and the manufacturer's total income is at the lowest point of average cost. Attract capital and people