Respuesta :

Answer:

  • C and D

Step-by-step explanation:

  • A. Incorrect as the directions are not opposite.
  • B. Incorrect as - 40 - 10 = -50 m ≠ 0.
  • C. Correct as the same amount is added and subtracted, resulting in zero.
  • D. Correct as protons and electrons have opposite charges, their sum is neutral.