$A$ rope by which a calf is tied is increased from $12 \ m$ to $23 \ m$. How much additional grassy ground shall it graze? (in $m^2$)

If the sides of a rectangle are increased by $20 \%$,the percentage increase in its perimeter is

$A$ circular swimming pool is surrounded by a concrete wall $4 \ m$ wide. If the area of the concrete wall surrounding the pool is $11/25$ that of the pool,then the radius (in $m$) of the pool is

If the perimeter of an isosceles right triangle is $(6+3 \sqrt{2}) \text{ m}$,then the area of the triangle is ... $\text{m}^2$.

If the measures of a diagonal and the area of a rectangle are $25\, cm$ and $168\, cm^2$ respectively,what is the length of the rectangle? (in $cm$)

The diameters of two concentric circles are $8\, cm$ and $10\, cm$. The area of the region between them is