A clean manufacturing space in an industrial area with dimensions 400x400x60ft3 , need to be directly illuminated by day light| using 400(4x4ft2) sky lights where each flat dome has a transmissivity of 60%. Consider the date is 2.00 PM on September 21st , sky is clear, and using the following assumptions: Depth of each well is 24 inches, the site is located 42o north latitude, walls reflectance is 30%, the well is painted with the same color and has the same reflectance of the ceiling of 80%, Rg=0.95 , no louvers at the base of the well, floor reflectance is 20% and finally the cleaning is done every 9 months. Km is Select one: а. 1.0 b. 0.50 c. 0.90 d. 0.70

A clean manufacturing space in an industrial area with dimensions 400x400x60ft3 , need to be directly illuminated by day light| using 400(4x4ft2) sky lights where each flat dome has a transmissivity of 60%. Consider the date is 2.00 PM on September 21st , sky is clear, and using the following assumptions: Depth of each well is 24 inches, the site is located 42o north latitude, walls reflectance is 30%, the well is painted with the same color and has the same reflectance of the ceiling of 80%, Rg=0.95 , no louvers at the base of the well, floor reflectance is 20% and finally the cleaning is done every 9 months. Km is Select one: а. 1.0 b. 0.50 c. 0.90 d. 0.70