It makes the data thet they collect more reliable so if they need the data again, they have already tested it a few times so therefor they know that it is right.
About 13.7 billion years ago
The Big Bang Theory states that the universe started about 13.7 billion years ago, and before that, everything was in 1 singularity.
Answer:
It makes it more difficult to move, making it stretch and exercise your muscles better becuse there is a resistant force to overcome.
Explanation:
-Sky :3