Which statement best describes how an existing theory is often affected by the development of new technology? An existing theory is thrown out and replaced with a completely new theory based on the new observations.
An existing theory is modified so that it can explain both the old and new observations.
An existing theory remains the same because a theory is a proven fact that is always true.
An existing theory is kept unchanged while a new theory is developed to explain the new observations.

i believe it is 40–40–20%

explanation:

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.