Question

why is 10 to power -12 and not -10​

Answer 1

1 metre =

6.685 × 10^-12 astronomical unit.

this is because 1AU is defined as the amount of distance travelled by light in one year.

Answer 2

Answer: it is the mean distance between centre of earth to centre of sun

as the distance  between centre of earth to centre of sun is in power of 10^12m so it is in power of 10^-12 and not -10

Explanation: