Respuesta :

altavistard

Answer:

C = 65.97 in; r = 10.5 in

Step-by-step explanation:

The circumference is C = πd.  Since the diameter is 21 in, the circumference is C = (3.14)(21 in) = 65.97 inches.

The radius is half the diameter:  

r = (21 in) / 2 = 10.5 in