BOSTON (AP) — Many of the first 100 prospective jurors questioned in the federal death penalty trial of Boston Marathon bombing suspect Dzhokhar Tsarnaev have said they can't be impartial because they already believe he's guilty or have a personal connection to the attack that would make it difficult to be objective. Three people were killed and more than 260 were injured when two bombs exploded near the marathon finish line on April 15, 2013.