A room measuring 12 × 20 ft is illuminated by 10 lamps rated 100 W ea – McqOptions

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1.	A room measuring 12 × 20 ft is illuminated by 10 lamps rated 100 W each with an efficiency of 12 lumens/watt. Assuming a depreciation factor of 1.5 and coefficient of utilization as 0.5, the illumination at the plane of the room is
A.	23.48 lumens/ft2
B.	16.67 lumens/ft2
C.	48.36 lumens/ft2
D.	34.54 lumens/ft2
Answer» C. 48.36 lumens/ft2

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