Answer:
Circle A= [tex]42\pi[/tex]
Circle B =[tex]56\pi[/tex]
Step-by-step explanation:
Circumference of a circle =[tex]2\pi r[/tex]
Since you are given the radius, you put it in place of r
Circle A = [tex]2 *\pi *28\\21*2 = 42\\\\42\pi[/tex]
Circle B= [tex]\\2*\pi *28\\28*2 =56\\56\pi\\\\\\[/tex]
