the sector of a circle has radius of 20 cm and central angle 135 o . find its perimeter ?
"perimeter of the sector = length of the arc + 2 ( radius ) = ( 135 / 360 * 2 * 22 / 7 * 20 ) + 2 ( 20 ) = 47.1 + 40 = 87.1 cm answer : b"
multiply(multiply(const_2, divide(multiply(subtract(20, const_3), const_2), add(const_4, const_3))), 20)