Answer:
Thinking about the good, becoming a good person, being around with good people
Explanation:
I put that because it change a person life of leaving the bad things behind by doing better things
Either mechanical or physical. I would say physical though.
Answer:
Facial expressions and Body language
The best answer for the blood vessels' valves would be these are veins that would then help in preventing the back flow of blood because the walls have small muscle to pump the blood back to the heart.Hope this is the answer.