Bank Clerk Questions

Plane and locomotive are synonyms to each other, Similarly, pilot and flight engineer are synonyms to each other. 

Hence, plane is to locomotive as pilot is to engineer.

The statement doesn't give any clue to the use of language. Hence a is not implicit.
b is also not implicit because in the sentence 'only' indicates false meaning.

First is a group of the second.

Hence, Archipelago : Islands :: Massif : Mountains.

Given speed of the person = 8 1/2 = 17/2 kmph
Let the speed of the stream = x kmph
speed of upstream = 17/2 - x
speed of downstream = 17/2 + x
But given that,
2(17/2 - x) = 17/2 + x
=> 3x = 17/2
=> x = 2.83 kmph.

Second is obtained from the first.

Silico Sapiens generally refers to robots.

Because each vertice of the square is the center of a circle
(1/4) part of the total area of each circle inside of the square.
(3/4) part of the total area of each circle outside of the square.
Thus total area outside the square is 434×227×3.5×3.5 = 115.3955 sq cm.

12 year old Manish is three times as old as his brother Rajeev who must be 4 years old.
Diff in ages = 8 years.
when Rajeev will become 8 years old, Manish will be 16 yrs old and he will be twice as old as Rajeev.