#### Answer

Circumference = $20\pi \approx 62.8$ meters
Area = $100\pi \approx 314.2$ square meters

#### Work Step by Step

RECALL:
In a circle:
(1) Circumference = $C = 2\pi{r}$
(2) Area = $A = \pi{r^2}$
(3) Radius = $r = \frac{d}{2}$
where r = radius and d = diameter
The given circle has a diameter of 20 meters.
Since the radius is equal to half of the diameter, the radius of the circle is:
$r = \frac{20}{2} = 10$ meters
Solve for the circumference and the area using formulas (1) and (2), respectively, to obtain:
Circumference = $2\pi(10) = 20\pi \approx 62.8$ meters
Area = $\pi(10^2) = \pi(100) = 100\pi \approx 314.2$ square meters