If the perimeter of a triangle is 12 unit and it in radius is 1 unit, then its area is

IF the area of a triangle is 6 sq.unit and its in radius 2 unit then its perimeter is

If the area of a triangle is 6.sq units and its inradius is 2 units then its perimeter is

If the sides of triangle be 15 units , 12 units and 9 units then the area (in sq. units) of the triangle is-

If the area of a triangle is 81 square cm and its perimeter is 27 cm, then find its in-radius in centi-metres.