The distance between Earth and the Moon was determined by measuring the time it took for light waves from Earth to travel to the Moon and back. Why was it not possible to use sound waves for this experiment? A Sound waves must move through a substance. B Sound waves would change frequency on the return to Earth. C Sound waves move too slowly for the technique to be accurate. D Sound waves move more slowly in Earth’s atmosphere than in space I NEED HELP ASAP

Option A - Sound waves must move through a substance

Explanation:

Unlike light waves, sound waves must travel through a medium/substance for such a medium to vibrate and then produce sound.

As a matter of fact sound can't travel through empty space.

Thus, looking at the options given, the correct one is:

Sound waves must move through a substance which is Option A

a long strand of spaghetti is folded once. if this is cut 20 times, how many pieces of spaghetti will there be? a long strand of spaghetti is folded once. if this is cut 20 times, how many pieces of spaghetti will there be? a long strand of spaghetti is folded once. if this is cut 20 times, how many pieces of spaghetti will there be? a long strand of spaghetti is folded once. if this is cut 20 times, how many pieces of spaghetti will there be? a long strand of spaghetti is folded once. if this is cut 20 times, how many pieces of spaghetti will there be?

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positive reinforcement? ?