The general equation of the circle is:

(h,k) is the center of the circle and r is the radius. We are given the coordinates of the center. So we can write the equation of the circle as:

In order to complete the equation, we need the radius of the circle. Using the given point we can find the radius. Using the point in the above equation, we get:

Thus the value of r² is 125. Using the value in equation of the circle, we get:

The radius of the circle is √125.
F(x)=4-2x+x^2
=4-1+1-x-x+x^2
=3+(1-x) - x(1-x)
= 3+(1-x) (1-x)
= 3 + (1 - x)^2
f(x) = (1 - x)^2 + 3
A and C are the only ones who could work...
Because 16+16=32 2+2=4 so 4 counselors to 32 campers
16+16+16=48 and 2+2+2=6 so 48 campers to 6 counselors could also work.
The answer is 20°C if you live in a very cold place so yah