The task is to generate the correct answer for a given math problem.

[Q]: Problem: a cistern 5 m long and 4 m wide contains water up to a depth of 1 m 25 cm . the total area of the wet surface is :
[A]: 42.5 m 2

[Q]: Problem: if a 1 mm thick paper is folded so that the area is halved at every fold , then what would be the thickness of the pile after 50 folds ?
[A]: 1 billion km', 'e ) none'

[Q]: Problem: in an office , totally there are 2800 employees and 25 % of the total employees are males . 30 % of the males in the office are at - least 50 years old . find the number of males aged below 50 years ?
[A]:
490