Answer: 78.5 units^2
Step-by-step explanation:
The area of the circle is equal to pi*radius^2.
The diameter is double the radius, which means the radius is 10/2 = 5.
Therefore, the area is pi*5^2 = 25pi.
We use 3.14 for pi and we get 25*3.14 = 78.5 units^2
