Answer: A) Acid rain Explanation: Secondary pollutants include ozone, which is formed when hydrocarbons (HC) and nitrogen oxides (NOx) combine in the presence of sunlight.   Whereas Primary pollutant are those pollutants that are directly emitted from their sources, like CO2, CO, SO2 as these gases are directly emitted form burning of fossil fuels.   Acid rain, which is formed when sulfur dioxide or nitrogen oxides react with water, sulfuric acid etc.   Hence, Acidrain is a secondary air pollutant.

Answer: A) 1987, Kolkata - India Explanation: Australia won the 1987/88 Reliance World Cup against England held in Kolkata, India.

Answer: D) 50 mts Explanation: Let the length of each train be x mts. Then, distance covered = 2x mts. Relative speed = 36 - 26 = 10 km/hr. = 10 x 5/18 = 25/9 m/sec. 2x/36 = 25/9 => x = 50 mts.

Answer: D) 104 Explanation: In normal we have 104 Weekend Days. We know that a Each normal year has 365 days or 52 weeks plus one day, and each week has two weekend days, which means there are approximately 104 weekend days each year. Whereas in a leap year we have 366 days it adds one more day to the year. And what makes the change is the starting day of the year.

Answer: C) China Explanation: China's amphibian aircraft, which is stated to be the world's largest, has successfully passed engine tests and is expected to make its maiden flight in the first half of the year 2017.

Answer: C) 32 Explanation: 32oFWe know that T(°F) = T(°C) × 1.8 + 3232(°F) = 0(°C)

Answer: D) All the above Explanation: An interest group is an organization whose members share common concerns and try to influence government policies affecting those concerns. Interest groups are also known as lobbies.

Answer: A) Argon Explanation: The most common gas people breathe from clean air is nitrogen. Air is a mixture of gases, and the air on Earth contains about 78 percent nitrogen and about 21 percent oxygen. Argon, carbon dioxide neon, helium, methane, krypton, hydrogen and xenon are in much smaller amounts.