Because we're creating a 95% confidence interval, this means we have two tails of 2.5%. When we look up 0.025 in the Z table (click to open) , we find that it corresponds to a z-score of 1.96. After plugging everything into the equation, we find a lower bound of 480.8 and an upper bound of 559.2.
As already noted, the speed of light (expressed in meters per second) means that light travels a distance of 9,460,528,000,000 km (or 5,878,499,817,000 miles) in a single year. This distance is known as a âlight yearâ, and is used to measure objects in the Universe that are at a considerable distances from us.
Best Answer: A light-year is the distance that light travels in one year. the speed of light is 299,792,458 metres per second which is about 371 million mph. Alpha Centtauri is 4.37 light years away so if you were to travel at the speed of light it would take you 4.37 years to get there from earth.