Environmental Engineering

A. 1 minute
B. 5 minutes
C. 2-4 hours
D. 12 hours

A. aerobic only
B. anaerobic only
C. aerobic in lower compartment and anaerobic in upper compartment
D. anaerobic in lower compartment and aerobic in upper compartment

A. 4-8 hours
B. 24 hours
C. 10 to 15 days
D. 3 months

A. large area is required for construction
B. maintenance and operation cost are high
C. BOD removal is very low
D. none of the above

A. percentage of sludge by volume to percentage of suspended solids by weight
B. percentage of sludge by volume to percentage of total solids by weight
C. percentage of suspended solids by weight to percentage of sludge by volume
D. percentage of total solids by weight to percentage of sludge by volume

A. 0
B. 1
C. infinity
D. none of the above

A. waste pipe
B. soil pipe
C. vent pipe
D. antisiphonage pipe

A. parasitic
B. saprophytic
C. pathogenic
D. anaerobic

A. vent pipe
B. antisiphonage pipe
C. waste pipe
D. soil pipe

A. reducing the excessive flow in sewers
B. disposing of sludge
C. increasing the capacity of storage re-servoirs
D. increasing flow of sewage through imhoff tanks