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.
The cost of an active Radon Mitigation System is typically between $800 to $1200 for installation, (*based on a single suction point) and the energy cost for running the Radon Mitigation System will average about $65 - $100 per year.*Special thanks to U of I & the IEMA for these facts on Radon. Radon comes from the natural breakdown of uranium and enters homes, schools and other buildings from the soil. 2  Elevated indoor levels are found in every state in the US, and in every county in Illinois. 3  Radon is by far the greatest single source of radiation exposure to the general public.