If it’s loud enough for your family to hear it, it’s best you turn it down. It could cause permanent damage to your ear drums if it’s loud enough and you could start to lose your hearing. So if your family were to tell you to turn it down, you should probably just turn it down!
Think about how each of noise, heat, visible light, radiation and atmospheric shock waves travel. Which ones require air particles to travel?
A vacuum has no air particles within it, it is completely empty.
Therefore, any of the above that requiring particles to travel will not be able to cross it and the observer will not experience it.
Answer:
1. 4 seconds
2. 4.1
Hope this helps:) Have a great day.