You have researched skylights for use in a factory building. Theresearch indicates that skylights can produce design illuminancewithin the building when the exterior illuminance reaches 4000footcandles. The factory building measures 160-ft wide x 250-ftlong. You require fifty footcandles as design illuminance. The sizeof the skylights will be 4-ft. wide x 8-ft. long. When new, it isestimated that each skylight will transmit about 50% of the lightthat hits it when the skylight is new. But the skylights get dirtyso because of this, 35% of the admitted light will be further lostdue to dirt buildup. Based on this given information, how manyskylights will be necessary to accomplish the daylighting mode forthis building? Â
