Which of the following fine dust removal equipments is the most efficient ?

A. Grey
B. Dark brown
C. Red
D. Black

A. Photochemical smog
B. Sulphur dioxide
C. Nitrogen dioxide
D. Dust particles

A. Dissolved gases
B. Suspended solids
C. Dissolved solids
D. None of these

A. Separation
B. Anaerobic decomposition
C. Aerobic decomposition
D. None of these

A. 10-7
B. 7 × 10-7
C. 107
D. 7 × 107

A. Moderately
B. Highly
C. Extremely
D. Very extremely