Answer:
See below
Step-by-step explanation:
Circle equation standard form
(x-h)^2 + ( y-k)^2 = r^2 h, k is the center
All are centered at 0,0
radii are sqrt(225) = 15 sqrt 49 = 7 and sqrt 178
The mean is the average of the numbers. It is easy to calculate: add up all the numbers, then divide by how many numbers there are.
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