Problem with taces on CSS and FAFSA

<p>On the CSS profile and FAFSA, I am asked for how much income tax my parents pay. The instructions say to look at line 55, but on my parents' 1040 form, that says 0. Initially, that's what I put, but CSS wouldn't allow it. I looked at the form closer and this is what I have: an alternative minimum tax as well as self-employment tax. Should i use one/both of these for that field?</p>

<p>Edit: Sorry about the title.. I'm in quite a rush to get this sorted out.</p>