A room, 10m x 5m x 4m, is to have an average illuminance of about 200 lx on a working plane
0.85 m above the floor. Assume the utilization factor to be 0.6 and allow for a maintenance factor
of 0.8. Calculate the number of 200-W lamps to be installed and indicate on a diagram a suitable
arrangement. Assume each lamp, when new, to emit 2700 lm and a spacing/height ratio of about
1.0. Also demonstrate (in a form of drawing) the spacing of luminaires for this scenario.