This question doesn't make sence to me could you explain
Answer:

Step-by-step explanation:
Given
See attachment for graph
Required
The domain of the graph
To do this, we simply write out the range of value of the x-coordinate.
From the attached graph, the x values are:
i.e. from 0 to 40 (both inclusive)
So, the domain is:

Answer:
2
Step-by-step explanation
Either your 5, your just trying brain.ly out, or your trolling don't care either way
Answer:
r^2=(A/pi)
Step-by-step explanation:
if A=pi*r^2 then maybe dividing by pi to get r^2 alone says r^2=(A/pi) or to get rid of the exponent you may square root each side so r=(sqrt(A/pi))