A perfect situation to use a proportion:
(3.9 x 10³³) / 1 = X / (2.45 x 10⁵) .
Solve that proportion for ' X ' in the usual way.
If you can't remember how to solve a proportion, then
THAT's what you have to go look up. It's much more
important to you right now than how much energy the
sun is putting out.
7.4 x 10⁴ mm is the same size as about 243 feet !
If the tracks on a DVD were that far apart, there would not be
room for very many tracks on a DVD. That's not reasonable.
If the tracks are 7.4 x 10⁻⁴ mm apart, then there are about
34,000 tracks in a stripe that's 1-inch wide. I have no idea
how they do this, but it's certainly more reasonable than the
other choice.
