A light year is the distance traveled by light in one year:
(a) Express this distance in meters and in kilometers. Use the average length of a year as described in the previous problem. How many significant digits can be given?
(b) Express a light year in miles.

Previous Problem

Find the average length of a century in seconds and in minutes. Use the rule that a year ending in 00 is not a leap year unless the year is divisible by 400, in which case it is a leap year. Therefore, in four centuries there will by 97 leap years. Find the number of minutes in a microcentury.