Problem: the parameter of a square is equal to the perimeter of a rectangle of length 4 cm and breadth 2 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 ) 4.51 , b ) 4.71 , c ) 4.32 , d ) 4.21 , e ) 4.68
b