If the perimeter of a potracter is 72 cm , calculate its area ?

As protector is a semicircle, so its perimeter  = perimeter of half of circle + 2(radius).
As Circle of radius R has circumference of 2πR so circumference of semicircle = πR
Hence the perimeter = πR + 2R = 72cm.
so R(π+2) = 72
R = 72/(π+2) = 14.007cm

So the Area of the semi-circle = πR² /2 = 3.14 ⨯(14.00)² /2 =307.28cm²