Answer: A) Air pollution Explanation: 1. Lichens are plants that grow in exposed places such as rocks or tree bark.   2.  Lichens are widely used as environmental indicators or bio-indicators. They can be used as air pollution indicators, especially of the concentration of sulfur-di-oxide in the atmosphere.     3. They need to be very good at absorbing water and nutrients to grow there.

Answer: D) 320 m Explanation: Relative speed = (72 - 36) x 5/18 = 2 x 5 = 10 mps.Distance covered in 32 sec = 32 x 10 = 320 m. The length of the faster train = 320 m.

Answer: A) 5 km Explanation:

Answer: B) Uncle and Aunt Explanation: Daughter of your mother's father's mother => Maternal grandmother => Renu's Aunt. Hence, Laxmi is Renu's Aunt and Vishal is Renu's Uncle.

Answer: A) Saturday Explanation: 350 days, 350/7 = 50, no odd days, so it will be a Saturday.

Answer: C) 1 Explanation: Given that, 4198+612345+34866+2411+1 Now Power Cycle of 4 is 4, 6  6 is 6  8 is 8, 4, 2, 6 1 is 1   4198- 198 is even number , So the unit digit value is 6    612345 - It is always 6   34866-  66/4 the remainder is 2 , So the second value is 4   2411- 11 is odd number, So the unit digit value is 4   1 - It is always 1  Total = 21   Therefore, The unit digit is 1

Answer: A) Fourth generation Explanation: Microprocessors are used in the computers of fourth generation computers. Personal microcomputers were possible due to the microprocessors.   Microprocessors further revolutionized the development of computers.   The first microprocessor called Intel 4004 was developed by American Intel Corporation in 1971.

Answer: A) 27 sec Explanation: Time taken to meet for the first time anywhere on the track = length of the track / relative speed = 300 / (15 + 25)5/18 = 300x 18 / 40 x 5 = 27 seconds.