The focal length of a lens determines the magnification at which it images distant objects. It is equal to the distance between the image plane and a pinhole that images distant objects the same size as the lens in question.hen a lens is used to form an image of some object, the distance from the object to the lens u, the distance from the lens to the image v, and the focal length f are related by. The focal length of a thin lens can be easily measured by using it to form an image of a distant light source on a screen.
The Killing Fields (Khmer: áá¶ááá·áá¶á viel pi-kÊ°iet) are a number of sites in Cambodia where collectively more than a million people were killed and buried by the communist Khmer Rouge regime, during its rule of the country from 1975 to 1979, immediately after the end of the Cambodian Civil War (1970â1975).
Anything you put it in the toilet affects the leach field. Also known as a drain field or soil absorption system, leach fields are an integral part of a septic system. If the leach field fails, replacing it can be costly.The cost of a new leach field depends on various factors. If your leach field needs replacement, get estimates from several contractors.You might save a few thousand dollars that way.eplacement Costs. Although costs vary according to the size of the leach field, soils and costs of local permits, expect to pay between $5,000 and $20,000 for leach field replacement. It is the most expensive component of the septic system.