BHD is a leading manufacturing company. It has a warehouse space of 9,600 square metres with 30 warehouse staffs. The available working time for each warehouse staff is 6 days a week with 8 hours per day. The space utilisation is 70% and the labour utilisation is 75%. The average warehouse cost per month is $20,000, and the total sales revenue per year is $600,000. Current stock level is 400 units, and monthly sale is 6,000 units. a. What is the used space for this warehouse? How many hours are all the staffs actually working? b. What is percentage of cost of goods sold c. What is the stock cover in days for BHD?