एक आयताकार अवसादन टैंक (sedimentation tank) का आयतन 3000 m3 है। यदि प्रवेशी प्रवाह दर (influent flow rate) 600 m3/घंटा है, तो निरोध समय (detention time) क्या है?

A sample of water has calcium content of 60 mg/l as CaCO3 and magnesium content of 80 mg/l as CaCO3. What is the total hardness of water?

A water treatment plant with the capacity of 1,00,000 m3/day has filter boxes of size (area) 10 m × 10 m. If five filters are out of service, what should be the loading rate (in m3/day/m2) of the remaining filters to maintain the capacity of the plant, assuming 10 working filters in total capacity calculations?