if the area of a circle is 49 pi square feet , find its circumference .
"the area is given by pi * r * r . hence pi * r * r = 49 pi r * r = 49 ; hence r = 49 feet the circumference is given by 2 * pi * r = 2 * pi * 7 = 14 pi feet correct answer a"
circumface(sqrt(49))