A man walking at the rate of 6km per hour crosses a square field diagonally in 9 seconds the area of the field is  Pick one:
A) 110 sq . m  B) 111.5 aq . m  C) 112.5 sq . m  D) 114 sq . m  E) none of these

Rationale: explanation : distance covered in 9 seconds = ( 6 × 1000 / 3600 ) × 9 = 15 m diagonal of square field = 15 m side of square = a then diagonal of that square = √ 2 a hence area of the square = a 2 = ( 152 ) / 2 = 112.5 sq . m answer : option c
Answer: C