math  please help
posted by Deborah .
Which expression is equal to 1/8000 written in scientific notation?
A.8.0 x 10to the 3rd
B.1.25 x 10–4
C.125 x 10–5
D.1.25 x 10 the the 4th
I think it is A..?

1/8 = .125 = 1.25x10^1
but you are dividing by 8000, so the answer is 10^3 as big: 1.25x10^4. (B)