Find the perimeter of a regular hexagon with each side measuring 7.5 m.

The lengths of two sides of a triangle are 12 cm and 14 cm. The perimeter of the triangle is 36 cm. What is the length of its third side?

A piece of string is 30 cm long. What will be the length of each side if the string is used to form:

(i) a square?

(ii) an equilateral triangle?

(iii) a regular hexagon?

Find the cost of fencing a rectangular park of length 225 m and breadth 115 m at the rate of ₹ 13 per metre.