Explanation:
In local galactic group the force of expansion of universe is overcome by the force of attraction due to gravity. Best example is our own galaxy milky way and another giant galaxy in our local group Andromeda. Andromeda having enormous gravity is pulling milky way towards itself, overcoming the force of expansion.
So, there are possibilities of collision despite the expansion of universe at a rapid pace. It is estimated that the milky way and Andromeda will collide each other after about 50 billion years from now.
Answer: B. The particles mover faster.
The largest possible displacement on a circular track is the straight-line distance between the starting point and the point directly opposite it, half-way around the circle. That's the diameter of the track ... 204 meters.
It's difficult to measure that because it's hard to make sure it is only a uniform layer of gas in whatever you're measuring it in
