d.) a and b only
This is because sound needs a medium to travel. It can travel in a solid (the fastest) and air for example. Sound waves cannot propagate through a vacuum and since space is a vacuum the answer is a and b only.
90 kilograms hope this helps
They move c<span>onstantly and are attracted to one another. Describe solids, liquids, and gases in terms of shape and volume. Solids have </span>definite<span> shape and volume.</span>
Yes you are right because if both of the photons are the same nothing is really happening thereafter c is the correct answer.
Answer:
1s
Explanation:
The time going up equals the time going down. So if the total time was 2s, the time rising was half that, or 1s.
