Answer: A) Hydrogen sulphide Explanation:

Answer: B) 50 Explanation: Sony and her brother's age sum is 31Let Sony's mother's age be 'x'.Now the conditions given for both of their ages related to their mom is1/5(x-15) + 3/5(x-10) = 31x-15 + 3x-30 = 1554x-45 = 1554x = 200x = 50So, Mother's age = 50. Cross verification : 15 years ago age = 35 => Sony age = 710 years ago age = 40 => bro age = 24 Sum = 24 + 7 = 31.

Answer: A) 6CO2 + 6H2O -----> C6H12O6 + 6O2 Explanation: Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms activities.   Photosynthesis can be represented using a chemical equation.   The overall balanced equation is                 6CO2 +  6H2O   →Sunlight    C6H12O6   +   6O2Source of Carbon & Oxygen  + Source of Electrons & Hydrogen + Energy that drives Photosynthesis             ----> Sugar + Gas produced by splitting water.   Where  CO2 = carbon dioxide  H2O = waterC6H12O6 = glucose  O2 = oxygen.

Answer: A) 330/29 m/s Explanation: Second gun shot take 30 sec to reach rahul imples distance between two. given speed of sound = 330 m/s Now, distance = 330 m/s x 30 sec    Hence, speed of the bus = d/t = 330x30/(14x60 + 30) = 330/29 m/s.

Answer: A) if a > b Explanation: I.  (a - 3)(a - 4) = 0   => a = 3, 4   II.   (b - 2)(b - 1) = 0   => b = 1, 2   => a > b

Answer: A) 2 lit Explanation: Quantity of fruit juice in the mixture = 70 - [70 x (10/100) ]= 63 litres.   After adding water, juice would form 87.5% of the mixture.   Hence, if quantity of mixture after adding x liters of water, [(87.5) /100 ]*x = 63 => x = 72    Hence 72 - 70 = 2 litres of water must be added.

Answer: C) 960 km Explanation: 60(x + 1) = 64x X = 15 60 x 16 = 960 km

Answer: C) Stamps Explanation: Stamps are what travel around the worldstaying in one spot. Slippers and walking stick can also travel around the world but they will not stay at one spot. So they are eliminated.