Please help me understand what this question is asking

Please click on pic to open it

hi.. question as per attached

Refer to the National Electrical Code® or the working drawings when necessary. Where applicable, responses should be written in complete sentences. 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 x 18 ft (~3.7 m x ~5.5 m) with a 9 ft (2.8 m) 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 ft ( m). For problems 2-5, two luminaires, 8 ft (2.5 m) and 4 ft (1.2 m) in length with dimensions as shown in Figure 15-7, are to be installed in tandem (end to end). The end of the long luminaire is to be 2 ft (600 mm) from the wall. 2. The center of the outlet box should be roughed in at ft ( m) from the wall. 3. The first support should be installed at the wall. ft ( m) from 4. The second support should be installed at from the wall. ft ( m) 5. The final support should be installed at the wall. ft…

Please help with full explanation:

How did you find the angles? Also my computer says the answer to (a.) is incorrect.