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.
Thatâs very fast. If you could travel at the speed of light, you would be able to circle the Earthâs equator about 7.5 times in just one second! A light-second is the distance light travels in one second, or 7.5 times the distance around Earthâs equator. A light-year is the distance light travels in one year.