ok first set it up as a fraction. so it would like this (3.5*10-6)
(5.0*10-2) Divide 3.5/5= .7 then add the exponents which would -8
so your answer would be (.7*10-6) but its not in scientific notation so it would actually be (7*10-5) I got that answer by moving the decimal to the right once and decreasing the exponet by one.
