Answer and Explanation:
The item in this picture looks to be a train from the overhead view.
I think it is showing the cargo as well as the train itself.
Answer:
If you were to take a glass and put water a little amount in it there would be more room for the sound to vibrate , but if you put more water then there would be less room for it to vibrate creating a higher pitch.
In my opinion it would be stress because it stimulates a energy level to do the work more motivated.
