Answer: D) Methane Explanation: Methane is the main component of biogas and natural gas.

Answer: C) 108 m Explanation: We know the rule that,   At particular time for all object , ratio of height and shadow are same.   Let the height of the pole be 'H'   Then  188=H48   => H = 108 m.

Answer: B) 8 : 13 Explanation: To get the solution that contains 1 part of milk and two parts of water,they must be mixed in the ratio as7x+6x/5y+11y = 1/226x = 16yx/y = 16/26x/y = 8/13

On carefully inspecting this question, one can understand that there are two days which are important and these are: A. My Birthday. B. The day when I am making this statement. If you think for a while, you will understand that such statements can be made only around the year’s end. So, if my birthday is on 31 December, then I will be making this statement on 1 January. I will further explain using the following example: 1. Consider that today is 01 January 2017. 2. Then, the day before yesterday was 30 December 2016 and according to the question I was 25 then. 3. Yesterday was 31 December 2016, which happens to be my birthday too (Woohoo!), and my age increases by one to become 26. 4. I will turn 27 on my birthday this year (31 December 2017). 5. I will turn 28 on my birthday next year (31 December 2018). Now, if you read the question again, it will make more sense:   The day before yesterday(30 December 2016), I was 25 years old and next year(31 December 2018) I will be 28.

Answer: B) 30 min Explanation: Distance travelled by Ramu = 45 x 4 = 180 km Somu travelled the same distance in 6 hours. His speed = 180/6 = 30 km/hr Hence in the conditional case, Ramu's speed = 45 - 9 = 36 km/hr and Somu's speed = 30 + 10 = 40km/hr. Therefore travel time of Ramu and Somu would be 5 hours and 4.5 hours respectively. Hence difference in the time taken = 0.5 hours = 30 minutes.

Answer: B) Rs.17,500 Explanation: Let’s assume John bought the laptop for Rs. 100He then sells it to Mark at a loss of 20% => Rs. 80,Who consequently sells it to Kevin at a profit of 25% =>  Rs. 100Then, Kevin sells it back to Mark for Rs. 90 (Rs.4.50 for every Rs. 5 that he had paid initially), so he suffers a loss of Rs. 10Therefore, for Rs. 100 there is a loss of Rs. 10,Then for Rs. 1,75,000 there will be a loss of Rs. 17,500.

Answer: B) 30 years Explanation: Let Karan’s present age be x years and Shiva’s present age be y years.Then, according to the first condition,x - 10 = 3(y - 10) or x - 3y = - 20 ..(1) Now, Karan’s age after 10 years = (x + 10) yearsShiva’s age after 10 years = (y + 10)(x + 10) = 2 (y + 10) or x - 2y = 10 ..(2) Solving (1) and (2), we get x = 70 and y = 30Karan’s age = 70 years and Shiva’s age = 30 years.

Answer: A) 1 Explanation: Only one such symbol is there in the given arrangement. It is 4@5.