Quantitative Aptitude - Arithmetic Ability Questions

What is the area (in sq cm) of a circle whose circumference is 26.4 cm?

In the following question, four groups of three numbers are given. In each group the second and third number are related to the first number by a Logic/Rule/Relation. Three are similar on basis of same Logic/Rule/Relation. Select the odd one out from the given alternatives.

If x + y = 5, x3 + y3 = 35, then what is the positive difference between x and y?

A thief is stopped by a policeman from a distance of 400 metres. When the policeman starts the chase, the thief also starts running. Assuming the speed of the thief as 5 km/h and that of policeman as 9 km/h, how far the thief would have run, before he is over -taken by the policeman?

If 3a=4b=6c and a+b+c=279 then a2+b2+c2 is equal to

If the numbers  93, 204, 256 are arranged in ascending order, then the right arrangement is 

If 3x - 10 = -(2x + 5), then the numerical value of (x - 4)3 is

If x - 1/x = 1 then what is the value of 1x1x-1-1x+1+1x2+1-1x2-1?