Both. You can use it as singular or plural.
Answer:
The time it takes for light from stars to reach us is the distance to the star divided by this speed
Explanation:
light travels at 300,000 kilometers per second or 186,000 per second. The nearest star to us is the sun and it takes about 8.3 minutes for its light to reach us here on Earth
1 AU is 149597871 kilometers.

We solve

This gives us .3897114284... AU away from the sun.