Who do you think took Ms. C's lunch?

Then the answer would be d then

Answeroutward from: source;

The answer is 4f======since electrostatic force is given by    we let f be the electrostatic force when  r = 1 m    if we let  denote the electrostatic force when the distance is decreased so that r = 0.5m, then    we established earlier that f = kq₁q₂. therefore    the force will now be 4f.

Cis the answer  hope this : d