* Light-year: A light-year is the distance light travels in one year.

* Speed of light: The speed of light is approximately 299,792,458 meters per second.

Calculations:

1. Calculate the distance in meters:

- One year has 31,536,000 seconds (approximately).

- Distance traveled by light in one year: 299,792,458 m/s * 31,536,000 s = 9.461 × 10^15 meters

- Distance to the star: 6.5 light-years * 9.461 × 10^15 meters/light-year = 6.149 × 10^16 meters

2. Convert meters to kilometers:

- 1 kilometer = 1000 meters

- Distance to the star: 6.149 × 10^16 meters / 1000 meters/km = 6.149 × 10^13 kilometers

Therefore, a star that is 6.5 light-years from Earth is approximately 6.149 × 10^13 kilometers away.