Answer: D) 6 days Explanation: 4/10 + 9/x = 1     => x = 15    Then both can do in  1/10 + 1/15 = 1/6     => 6 days

Answer: C) 17 Explanation: The pattern is 32+42=52,  52+122=132, 72+242=252  The next number = 82+152=172  i.e. 17

Answer: B) VPCVZRL Explanation: ROUTINE IS 7 LETTER WORD.. (1st=R,2nd=O,3rd=U,4th=T,5th=I,6th=N,7th=E)1st and 3rd letter interchanging. (UORTINE)5th and 7th letter interchanging. (UORTENI)1st letter shifting one after that (VORTENI)2nd letter shifting two befor that (VMRTENI)3rd letter remains same (VMRTENI)4th letter(total alphabets - current)+1(26 - 20)+1= 7.(i.e) G (VMRGFNI)5th letter shifting one after that (VMRGFNI)6th letter shifting two befor that (VMRGFLI)7th letter remains same (VMRGFLILike that,CRUELTY IS 7 LETTER WORD.. (1st=C,2nd=R,3rd=U,4th=E,5th=L,6th=T,7th=Y)1st and 3rd letter interchanging. (URCELTY)5th and 7th letter interchanging. (URCEYTL)1st letter shifting one after that (VRCEYTL)2nd letter shifting two befor that (VPCEYTL)3rd letter remains same (VPCEYTL)4th letter (total alphabets - current)+1(26 - 5)+1= 22.(i.e) V (VPCVYTL) 5th letter shifting one after that (VPCVZTL)6th letter shifting two befor that (VPCVZRL)7th letter remains same (VPCVZRL).

Answer: D) Nest Explanation: Here the first two words are synonyms. Similarly, Eyrie means a large nest. So, the synonym of Eyrie is nest.   Hence, Convent : Cloister :: Eyrie : Nest.

Answer: D) ²²C₁₀ - 1 Explanation: The total number of ways of forming the group of ten representatives is ²²C₁₀. The total number of ways of forming the group that consists of no seniors is ¹⁰C₁₀ = 1 way The required number of ways = ²²C₁₀ - 1

Answer: B) Band width Explanation: The path that data takes from source to destination is called a Channel. A channel is a communication medium. A channel has a certain capacity for transmitting information.    The "capacity" of a channel is the theoretical upper-limit to the bit rate over a given channel that will result in negligible errors. Channel capacity is often measured by its Bandwidth in Hz or its data rate in bits per second.

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) 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.