title: How do I export a higher resolution image of a Mathematica Graph object?
body: <p>How do I export a re-sized version of the output I get from a call to <code>GraphPlot</code> 
  (or <code>TreePlot</code> if they produce different output) to a jpg file?<br>
  Currently, I'm simply calling <code>Export[file_name, G]</code>
  where <code>G</code> is the result from a call to something like <code>GraphPlot</code>. 
  I'm using Microsoft office picture manager to view the jpgs, 
  but re-scaling them there yields unsatisfactory results due to poor resolution 
  (the graph I'm trying to plot has strings as labels which can't be made out after rescaling this way). I would like to be able to choose the size/resolution of the rendered jpg.</p>