Final answer:
The Astronomical Unit (AU) is typically used to measure distances within the Solar System, whereas light-years are used for distances on an interstellar scale, such as to other galaxies.
Step-by-step explanation:
The unit of measurement typically used to determine distances in our Solar System is the Astronomical Unit (AU). One AU is the average distance from Earth to the Sun, which is about 150 million kilometers (1.5 × 108 kilometers). This is useful for measuring distances within the solar system because it is a scale that is well suited to the vast distances involved. Light-years, on the other hand, are commonly used to measure distances outside our solar system, such as the distance to other stars and galaxies. For example, the Andromeda Galaxy is 2.00× 106 light-years away. A light-year is the distance light travels in one year, which is approximately 9.461 × 1015 meters.