a light-year is the distance light travels in one year (at speed=2.998x108m/s).
1) Find how many meters are there in 1.00 light years?
2) An astronomical unit (AU) is the average distance from the sun to earth, 1.50x 108 kilometers. Find how many AU are there in 1.00 light years?
3) Find what is the speed of light in AU/h?