The light rays are refracted by the cornea onto the lens. The light rays are refracted a second time whilst passing through the lens and focussed onto the retina â the light sensitive part of the eye. The image formed on the retina is inverted (upside down) and real (the light rays travel through the image).
Nationally, professionally-installed radon mitigation system costs average $1,200, but range from $800 to $1,200 in Colorado, assuming there aren't any problems encountered during installation.*. Costs are highly dependent on what is required to vent the radon and how to route it through the house.
Additional costs: Ground water wells can also be tested for radon, then, if needed, can get a water radon mitigation system installed. Installing a water radon mitigation system runs from $1,000-$4,500, and maintenance runs $0 to $150 annually.