You are required to design lighting system for a large space to meet the uniformity and illumination requirements. This is for an office space of 20m by 15m area with a ceiling hight of 3.5m. The working surface is 0.70m high. The reflectance of the space is defined by 0.7 ceiling, 0.5 walls and 0.2 floor. The average daily usage of the lamp is 15 hours. The Luminaire units used are dust proof and has 0.6x0.6 m illumination opening. Each luminaire contains 3 LED tubes of 20watt per tube rating with efficacy of 150 Lumen/watt. The Luminaire's walls are micro-prism polycarbonate diffusers. Light Output Ratio LOR=0.80. The required maintained average illuminance at the working height is E = 500 Lux. The space to height ratio SHR@70% for both directions = 1.5. The Office and Luminaries cleaned every year. This is to satisfy the Glare Requirement. The LLMF for the L70 50,000h lamp used is 0.9. Use the LED lamp L70 50,000h characteristic curve, and the LMF, RSMF and Utilization Factors data tables offered by Appendix1 below for your solution and work out the followings: 1. The number of luminaires needed and possible uniform distribution over the space. 2. The number of luminaires required to satisfy the illumination at workspace level of E=500 Lux. 3. The workspace illumination that results from using the arrangements you have decided on for the uniform distribution in 1 above.