Ambient noise level can be reduced by __________ decibels by planting trees (like coconut, neem etc.) near public utility buildings (like hospitals & schools). 43832 25-30 15-20 43961 TRUE ANSWER : ? YOUR ANSWER : ?
Workers working in __________ industry are most prone to white lung cancer. Asbestos Textile Limestone mining Coal mining TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following is not a source of ozone emission in the atmosphere? Dermatological photo-therapy equipments Refrigerators High voltage electrical equipments Xerox machines TRUE ANSWER : ? YOUR ANSWER : ?
Smog is not formed due to the presence of __________ in the atmosphere. SO₂ CO₂ NOx Any of these TRUE ANSWER : ? YOUR ANSWER : ?
Cleaning is done by(i) Scraping and removal in filters slow sand(ii) Back washing in slow sand filters(iii) Scraping and removal in filters rapid sand(iv) Back washing in rapid sand filtersThe correct answer is (ii) and (iv) (i) and (iv) (i) and (ii) (ii) and (iii) TRUE ANSWER : ? YOUR ANSWER : ?
Inhalation of silica dust by human being during hand drilling in mica mining, lead & zinc mining, silica refractory manufacture and in foundaries causes All of these Shortness of breath Tuberculosis Asphyxiation (suffocation) TRUE ANSWER : ? YOUR ANSWER : ?
Iron & manganese present as pollutant in water can not be removed by Lime soda process or manganese zeolite process Oxidation followed by settling & filtration Chlorination Ion exchange process TRUE ANSWER : ? YOUR ANSWER : ?
Which is the best and the most effective method for the removal of organic contaminant present in the polluted water in very small quantity (say < 200 mg/litre)? Biological oxidation pond Activated carbon adsorption Chemical coagulation Lagooning TRUE ANSWER : ? YOUR ANSWER : ?
Infective bacteria in water is killed by the __________ process. None of these Disinfection Sterilisation Aeration TRUE ANSWER : ? YOUR ANSWER : ?
__________ substances present in sewage are removed in grit chamber during sewage treatment. Inorganic Dissolved Organic Fatty TRUE ANSWER : ? YOUR ANSWER : ?