How many cat breeds are there in the world?

Hey.. ♥️♥️ me in solving this question

When you turn on a battery-operated device, an electrical circuit is

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve