Problem: the parameter of a square is equal to the perimeter of a rectangle of length 9 cm and breadth 6 cm . find the circumference of a semicircle whose diameter is equal to the side of the square . ( round off your answer to two decimal places ) ? 
Options: a ) 11.72 , b ) 11.52 , c ) 11.97 , d ) 10.91 , e ) 11.79
e