For problems 1,and 2,six luminaires,similar to Style E used in the Commercial Building,are to be installed in a room that is 12 ft by 18ft(3.7 by 5.5)with a 9 fit (2.8)floor -to ceiling height.The spacing ratio for the luminaire is 1:0 1. The maximum distance that the luminaires can be separated and achieve uniform illuminance is 9 ft ( 2.8 m)