A circle is inscribed in a square of side 14 cm. Find the area enclosed between the square and the circle.

The ratio between the diameters of two circles is 3 : 5. Find the ratio between their :

(i) radii

(ii) circumferences

(iii) areas

Calculate the area of a triangle whose sides are 13 cm, 5 cm and 12 cm. Hence, calculate the altitude corresponding to the longest side of this triangle. Leave your answer as a fraction.

Find the area of a triangle whose perimeter is 22 cm, one side is 9 cm and the difference of other two sides is 3 cm.