uses of profit and loss account Visual inspection is easy to find, if it is a gas pipe that breaks down to see if there is gasoline in the ground. Sunglasses allow better vision in bright daylight, and may protect one's eyes against damage from high levels of ultraviolet light. Typical sunglasses are darkened for protection against bright light or glare; some specialized glasses are clear in dark or indoor conditions, but turn into sunglasses when in bright light. Most sunglasses do not have corrective power in the lenses; however, special prescription sunglasses can be ordered. Specialized glasses may be used for viewing specific visual information (such as stereoscopy) or 3D glasses for viewing three-dimensional movies. Sometimes glasses with no corrective power in the lenses are worn simply for aesthetic or fashion purposes. Even with glasses used for vision correction, a wide range of designs are available for fashion purposes, using plastic, wire, and other materials. In the 18th century, the western countries successively carried out the industrial revolution, the universal adoption of large machinery, laid the foundation for the establishment of factory system. In 1771, British man Richard arkwright1732-1792 founded the first cotton-yarn factory in the city of kron. In the 1930s and 1940s, the factory system was established in Britain, Germany and other countries. The main sex of factory system is: to carry out large-scale intensive labor; Using big machine to improve efficiency production; Implement the employment system; The division of labor is deepening and production is socialized. The establishment of factory system marks the real birth of enterprises. The plan, which is applied to the organization as a whole, is called a strategic plan for the organization to set up overall goals and to seek the organization's place in the environment. The plan for the details of how the overall goal is implemented is called the job plan. The strategic plan and the job plan are different in terms of time frame, in terms of scope and whether they include a set of organizational goals that are known. Strategic planning tends to include persistent intervals of time, usually five years or more, covering a wide range of areas and does not specify specific details. Furthermore, an important task of the strategic plan is to set goals; The job plan assumes that the goal already exists, but only provides a way to achieve the goal.