Answer:
1. difference of light year and AU 2. difference of kilometers and AU
Step-by-step explanation:
1.A light year is the distance light travels in a year. ... One light year is almost six trillion miles. And an astronomical unit is the average distance between the earth and the sun. So the distance to the sun is by definition one AU.
2. More exactly, one astronomical unit (AU) = 92,955,807 miles (149,597,871 km). Earth's orbit around the sun isn't a perfect circle. So Earth's distance from the sun changes throughout the year. Astronomers give the Earth's changing distance throughout the year relative to the astronomical unit, to