If you were to divide the presentday universe into cubes whose sides are 10 million lightyears long, each cube would contain, on average, about one galaxy similar in size to the Milky Way. Now suppose you travel back in time, to an era when the average distance between galaxies is 0.24 of its current value, corresponding to a cosmological redshift z= 2.7. How many galaxies similar in size to the Milky Way would you expect to find, on average, in cubes of that same size?

Answertraveling around a circular trackexplanation"traveling around a circular track" is the best answer as you could be traveling around a circular track at a constant speed. your velocity would therefore have the same magnitude but will always be constantly direction. since acceleration is the rate of change of velocity, the rate of change will only involve the direction of velocity and not the magnitude.wrong choices: "an object at rest" does not accelerate at all"increasing speed while traveling around a curve" means that the acceleration will not be constant due to only change in direction; it will be constant due to both magnitude and direction"an object in free fall" does not necessarily change direction 

Answerthe valence of an element or radical is equal to the number of positive or negative charges on the ion.