4. The function A(r) = πr² gives the area of a circle with radius r. What is the context domain?
I only need help with #4 pls

Answer:
Domain = [0 , +∞)
Step-by-step explanation:
since r is the radius of a circle
Then
r must be a positive number.
Then
r ≥ 0
NOTE : if r = 0 ,then the circle reduces to a point .