Reason (R) : Thinning of the ozone layer allows excessive UV radiations to reach the surface of earth.
Answer: A is not correct but R is correct.
Reason (R) : Such pesticides are non-biodegradable.
Answer: Both A and R are correct and R is the correct explanation of A.
Reason (R) : High biological oxygen demand means low activity of bacteria in water.
Answer: Both A and R are not correct.
Answer: the reaction is endothermic
Answer: Mg
Answer: N2O5
Answer: Mesosphere
Answer: impurities’ coagulation
Answer: nuclear fusion
Answer: PAN
Answer: dissolved oxygen concentration below 5 ppm is ideal for the growth of fish
Answer: Freons
Answer: Chlorofluorocarbons
Answer: Troposphere
Answer: It has low concentration of oxidizing agent.
Answer: decrease in the amount of dissolved oxygen in water.
Answer: Ozone is not responsible for greenhouse effect.
Answer: Its main components are produced by the action of sunlight on emissions of automobiles and factories.
Answer: S02
Answer: A, B