Respuesta :

paulnneji

to find radius; 8.4/2,

  1. therefore 2×22/7×8.4/2×10.9=1079.76

misspandamail

Answer:

398.5

Step-by-step explanation:

a (surface area) = 2πrh + 2π[tex]r^{2}[/tex]

r (radius) = 8.4/2

r = 2.4

a = 2π (4.2 x 10.9) + 2π (4.2 x 4.2)

a = 2π x 45.78 + 2π x 17.64

a = 287.64 + 110.83

a = 398.5