X^2+ (y+8)^2 = 81.....this is C.
X^2 + y^2 + 16y +64=81 so x^2 + y^2 + 16y = 17.....this is D.
So I’d say C and D are correct
You add 70,50, and 90 together then you do seperately 30, and80 (add) lastly take that amount then divide that by your first sum
