V=\frac{4}{3}\pi r^3
V_1=\frac{4}{3}\pi 3^3
V_1=\frac{4}{3}\pi \cdot 27
V_1=36\pi[cm^3]
----
V_2=\frac{4}{3}\pi \cdot 5^3=\frac{4}{3}\pi \cdot 125
V_2=166,67 \pi [cm^3]
V_3=V_1+V_2=36 \pi + 166,67 \pi=202,67 \pi cm^3
\frac{4}{3} \pi r^3=202,67 \pi | / \pi
\frac{4}{3} r^3=202,67 |* 3
4r^3=202,67
r^3=202,67 /4
r=5,873...
r \approx 5,9 cm
P=4\pi r^2
P=4\pi \cdot 5,9^2
P=4\pi \cdot 34,81
P=139,24 \pi cm^2
\pi \approx 3,14
P \approx 437,2 cm^2