Question

da recede Va rog frumos

Answer 1

[tex]Aria\,bilei=64\pi\,=\, 4\pi{R^2}\;\;\Rightarrow\;\;R^2 = 64\pi:4\pi =\;16\;\;\boxed{R=4};\\ V_{bila}=\frac{4\pi{R^3}}{3}=\frac{4\cdot64}{3}\cdot\pi [/tex]

Answer 2

A = 64π = 4πr² => r = √64π : 4π =>  r = 4 cm

V = 4πr³/3 = 4π64/3 = 256/3 ≈ 85,(3) cm³

Obs. Am calculat π = 3,14