Answer:
Option A applies.
A. Greater than its escape speed from the mass within the volume
Explanation:
Here it is mentioned that the spherical volume is large enough for the space to be considered as homogeneous. Also, the pressure within the volume is negligible, so that will not result into the re collapse of the Universe. Now as per our knowing, Hubble's Law relates the average speed of the particle to the distance R between the Earth and the particle. So, if the particle's speed is greater than it's escape speed from the mass within the volume, then the Universe is bound to re collapse back again. Option A applies.
Better technology is helping us because we can see more stuff like the microscope we able to make assumptions based on what we saw.
To answer that question, we don't care what the highest and lowest
levels of the wave are, or how far apart they are. We only need to be
able to identify the highest point on the wave, and keep track of how
often those pass by us.
You said it takes 4 seconds for a complete wave to pass by.
Through the sheer power of intellect, I'm able to take that information
and calculate that 1/4 of the wave passes by in 1 second.
There's your frequency . . . 1/4 per second, or 0.25 Hz.
