The radius of a wheel is $1.4$ decimetre. How many times does it revolve during a journey of $0.66$ km?

If the sides of a triangle are doubled,its area

$A$ can go round a circular path $8$ times in $40$ minutes. If the diameter of the circle is increased to $10$ times the original diameter,then the time required by $A$ to go round the new path once,travelling at the same speed as before,is (in $min$)

If a square is inscribed in a circle,the ratio of the area of the circle and the square is

$A$ rectangular paper,when folded into two congruent parts,has a perimeter of $34\, cm$ for each part when folded along one set of sides and a perimeter of $38\, cm$ when folded along the other set of sides. What is the area of the original paper in $cm^2$?

The diagonal of a square field measures $50 \, m$. The area of the square field is.........$m^2$?