Web Site #4 (org.)

a) Yahoo!

b) I changed the search to( water contamination using fracking) I put this in the advanced search in Yahoo! and marked the .org domain

c) Lustgarten, Abrahm. ProPublica. "Scientific Study Links Flammable Drinking Water to Fracking." 9 May 2011.  Web. July 26, 2011 
<www.propublica.org/...flammable-​drinking-water-to-fracking>

d) This site is credible because it was written as recently as 2011, it had scientific data presented, and ProPublica is an independent, non profit newsource.