Answer
$A=4\pi \times0.5^2=1\pi$ square kilometers
$A\approx \frac{22}{7}\times 1= 3.1429$ square kilometers
$V=\frac{4}{3}\pi\times 0.5^3=0.16667\pi$ cubic kilometers
$V\approx \frac{22}{7}\times 0.16667=0.5238$ cubic kilometers
Work Step by Step
This solid is a sphere and its volume can be calculated as:
$V=\frac{4}{3}\pi r^3$ where r is the radius
Here:
$V=\frac{4}{3}\pi\times 0.5^3=0.16667\pi$ cubic kilometers.
$V\approx \frac{22}{7}\times 0.16667=0.5238$ cubic kilometers
The surface of a cylinder can be calculated as:
$A=4\pi r^2$
Here:
$A=4\pi \times0.5^2=1\pi$ square kilometers
$A\approx \frac{22}{7}\times 1= 3.1429$