Question

ASAP mark Brainliest, Which of these details does not support the central idea central idea: even though one of Edison’s investors failed, he never stopped trying out new ideas

Answer 1

I’m pretty certain it’s d because it does not state anywhere that the sound waves are not powerful enough to make the vocal engine useful. hope this helps brainlist would be much appreciated :)

Answer 2

The answer is the 4th option