You answer is anything you want it to be since you didn't site units in your question. 5.55E-6 or 5.55E+6 WHAT?
I think it is likely you meant 5.55u without the dash (or minus sign).
5.55u = 1.55E-6 meters.
5.55 - u = 5.55 WHAT = 1E-6 = ?
Is 5.55-µ equal 5.55*10^-6 or 5.55*10^+6?
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