Answer:
Statement that is true about electromagnetic and mechanical waves is:
Option B: Mechanical waves must travel through a medium, but electromagnetic waves do not require a medium to travel.
Explanation:
'Electromagnetic' waves do not need any medium to travel whereas 'mechanical waves' need a medium or matter for transmission. Electromagnetic waves are produced by the 'vibrations' of the charged particles. They can even travel in vacuum.
On the contrary, mechanical waves are caused by the 'wave amplitude'. Mechanical wave can travel in solid, liquid and gas and are considered to be periodic disturbance.
Thus, Option B is the most statement apt explaining the difference between electromagnetic and mechanical waves.
During the 1950s, as a result of war and conquering, the status of most countries in Eastern Europe is that they became satellite countries of the Soviet Union at that time. Most countries that neighbor the Soviet Union were heavily influenced by it in terms of politics, military and economy.
Answer:I think the answers would be A(maybe),B,and D.
Explanation:
I'm not sure about A. B because it stop people from entering easily. D because people can put cameras on them. I'm most sure about B though. I hoped this helped.
Answer:
someone who is a hero is someone who has helped me through hard times
Explanation:
Answer: Powhatan, also called Wahunsenacah or Wahunsenacawh
Explanation: I searched it