she wed t the p he held her hand. we gave her water -- beca as soon as we cleared an area for her, she tried to walk out on her own. >> reporter: rescue teams used dogs, motion detectors, sona and tracking cell phone signals to owners. to know where to dig. among the six dead, ann bryant, a 24-year-old arts student shopping at the thrift store, she was crushed. and the woman rescued was lucky, myra plekam, trapped 13 hours. others survived in collapsed buildings far longer. in the 2010 haiti earthquake, a child survived eig in rubble. in tier this year, a woman lived rmey co this year, a woman lived bangladesh. experts point to the rule of threes as the keys to survival. you can't go more than three minutes without air. more than three days without water. three weeks without food. here in philadelphia, the big pere in philadelphia, the big