Engineering Statement of Purpose Questions

<p>I'm wrapping up my SOP for a few of my graduate schools and I have a few questions. This SOP is for engineering grad school.</p>

<ol>
<li><p>Roughly how long should the SOP be? I cannot find any direct answer to this question on the websites of the schools I’m applying to.</p></li>
<li><p>Should I mention specific research that a professor is doing that interested me? I was thinking of doing this but I feel this would be a bit too specific/thorough for a letter that is supposeto be relatively short. Did any of you do this?</p></li>
<li><p>How important is the SOP? I’ve heard that some professors merely scan thru them while others use it as a deciding factor?</p></li>
</ol>

<p>Thanks in advance!</p>