A. The center of the circle is the midpoint of the given endpoints. That is,
x-coordinate = (-7 + 3) / 2 = -2
y-coordinate = (-10 + 2) = -4
The coordinates are (-2,-4)
B. The radius of the circle is the distance between the center and one of the points.
r = sqrt ((-10 - -2)^2 + ( -7 - -4)^2) = sqrt of 73
C. The equation of the circle is written through the equation,
(x - -2)^2 + (y - -4)^2 = (sqrt of 73)^2