Check the fundamental theorem for gradients using tx2 +4xy + 2yz3, the points a - (0,0,0), b - (1,1,1), and the following three paths: c. the parabolic path z x, y-x.

the answer is neither ball has a charge.

because if they were both positively charged, they will repel each other.

if they were positively and negatively charged, they will seek.

force tends to be low and long diustance masses are high

because if the tool that you are using is not balanced it there would be false mass.