1. A filter is 40 ft long by 20 ft wide. During a test of flow rate, the influent valve to the filter is closed for 6 minutes. The water level drop during this period is 16 inches. What is the filtration rate for the filter in gpm/ft2?

2. A metropolitan has a population of 100,000 with an average rate of demand of 160 liters per head per day. What is the actual number of filters required if the size of each filter is 9 m * 5 m? Assume the average filtration rate as 4500 liters per hour per m2 and one units as standby?

3. What do you mean by Effective Size and Uniformity Coefficient? Explain