Question

The spiral galaxy in the Andromeda constellation is about 2 × 1019 km away from us. How many light-years is this?

1. 3.48837 × 106 c.
2. 1.62791 × 106 c.
3. 7.39958 × 105 c.
4. 1.08668 × 107 c.
5. 2.11416 × 106 c.
6. 5.09514 × 106 c.

Answer 1

5. 2.11416 × 10^6 c.

Step-by-step explanation:

First thing to Know is the conversion factor from km to light year which is

1 kilometre =

1.057 × 10-13 light-year.

So

2 × 10^19 km is equal to

2 × 10^19 * 1.057 × 10-13

2 × 10^19 km = 2.114 * 10^6c