B, because if all galaxies are moving away then as the ball expands the galaxies will expand outwards as well. study theorys, its a much broader topic but this is the short and sweet answer
Linear momentum is mass multiplied by velocity, so it follows that angular momentum is the moment of inertia, measured in kilogram meters squared, multiplied by angular velocity, measured in radians per second. Radians are just an alternative to degrees.
It would be air temperature.