how much does a school principal earn The response to single factor value is trend. The tendency is the selection bias produced by the stimulation of the organism on a single environmental factor, which is the directional response form of the organism to the external stimulus, including the two basic forms of orientation and avoidance. The tropism has the tendency of phototropism, thermal tendency, wetness, tendency, and oxygenicity. It has the avoidance of light, heat, moisture, anaerobic and so on. For example, the acidity of paramecium, the thermal tendency of bedbugs and the phototropism of insects. The trend is the common response of low biological cells, biological tissues and protozoa. Tropism is in a series of internal inductance organically combined in a certain direction, to form a structure of ordering, and external single environment factor to form a single reaction, the biological function between the body and the external environment on the coherent function, to accelerate the ordering of the body development. When this series of inductivity is combined in a positive way, the tendency is formed. When this series of induction is combined in reverse, it forms a negative trend - the avoidance. In summary, the trend is the most elementary preordinate response to the external things of single factor value. As the center of global automotive engine research and development and production, Britain's powertrain design has always maintained the world's leading level, especially in engine design. In 2013, the UK produced 2.55 million engines, accounting for 30 per cent of total European engine production, with 62 per cent of the engines exported to more than 100 countries. Phoenix iMarkets compiled from ZeroHedge, according to government data compiled by Labyrinth consulting services, the growth trend of U.S. personal vehicle mileage (VMT) has been steady since June 2017. The possibility of a halt to growth in U.S. personal vehicle miles (VMT) has been around since the start of 2014, which could signal a slowdown in crude oil consumption. Most western interest-rate determinism focuses on the analysis of supply and demand comparisons, arguing that interest rates are a price. The difference lies in what supply and demand determines interest rates. For example, Marshall's real interest rate theory emphasizes the real factors of non-monetary factors - productivity and the role of economy in determining interest rate decisions. Productivity is expressed by marginal propensity to invest, and the marginal propensity to save is expressed. New IRS Commissioner, John Koskinen, in the public announcement states, "We're expanding the Streamlined Procedures to pay for a significantly broader band of US taxpayers we presume are on the market who have still did not disclose their foreign accounts but who were not willfully evading their tax obligations. To encourage these taxpayers to come forward, we're expanding the eligibility criteria, eliminating a cap for the quantity of tax owed to qualify for the program, and getting rid of a questionnaire that applicants were required to complete."