Solution: as long as the gasoline in the tank is exhausted, the extra gasoline vapor in the tank can be fired into the cylinder by the negative pressure of the engine, and no gasoline vapor will overflow. On Wednesday, on the first four shopping days of Christmas, upscale stores were discounting heavily, including most of the fashion retailers. H&M offers discounts of up to 60%, while Debenhams, Fraser, French connections, gaps, new faces and Dorothy Perkins offer discounts of up to 50%. When IHS Markit produced a euro-area purchasing managers index of 58, more than most economists had forecast, it was at its highest level since February 2011. Any score above 50 indicates growth. When IHS Markit produced a euro-area purchasing managers index of 58, more than most economists had forecast, it was at its highest level since February 2011. Any score above 50 indicates growth. The response to multilayered values is rational. Rational (including abstract thinking with image thinking) is higher animals, are now known to have intelligent human only) on the basis of intellectual responses, to the further development of it by means of language, text or image will intellectual formed by various basic concept and basic image fixed in the form of the second signal system in the brain, and within the brain to be more complex, the deeper, longer series "sex", "rigid instinct", "elastic instinct" and "intellectual" and other forms of reaction. Among them, the cognition of the relation between the basic concepts forms the abstract thinking, and the person's understanding of the relation between the basic images forms the image thinking. Rationality is human to the second signal system of "reflection" type of reaction activity, it can find out the basic concept and basic image, more general internal relation and essence difference between to discover things between the movement of more general and more abstract and change rule. For example, people form "water" and "to..." through the practice of production and life. To ", "low" and "flow", the concept of nouns, prepositions, adjectives, verbs, between these concepts through a certain form of conditioned reflex established a mutual connection, thus obtained the "water flows downwards" such a logic rules.