World environment day is observed every year on the 5th of___________________?

Related Mcqs:

For existence of aquatic life in water, the dissolved oxygen content in it, should not be less than ______________ ppm?

A. 10000 B. 5 C. 500 D. 1000...

Removal of ______________ results from the disinfection of water?

A. Turbidity B. Odour C. Hardness D. Bacteria...

Iron & manganese present as pollutant in water cannot be removed by__________________?

A. Ion exchange process B. Oxidation followed by settling & filtration C. Lime soda process or manganese zeolite process D. Chlorination...

Pick out the wrong statement. A. Caustic embrittlement of boiler’s metallic parts is caused by high concentration of caustic soda in boiler feed water___________________?

B. Cooling and freezing of water kills the bacteria present in it C. With increasing boiler operating pressure of steam, the maximum allowable concentration of silica in feed water goes on decreasing D. Dissolved oxygen content in high pressure boiler feed water should be nil...

Pollution by particulate matter emission in the atmosphere does not take place during metal____________________?

A. Grinding B. Machining C. Cutting D. Polishing...