Respuesta :

Answer:

radius: 4.2 cm

circumference: 26.376 cm^2

area: 55.3896 cm^2

Step-by-step explanation:

radius is half the diameter so 8.4/2 = 4.2

circumference: C = (2)(pi)(r) ---> (2)(3.14)(4.2) --> 26.376

area: (pi)(r ^2) --> (3.14)(4.2^2) --> 55.3896