Bernie Sanders – Anderson Cooper profiles the self-described democratic socialist senator from Vermont, who currently leads the polls for the Democratic presidential nomination. 298 Counts of Murder – Six years ago, a missile brought down Malaysia Flight 17 over eastern Ukraine, killing 298 on board. Next month, four men, three of them Russian, go on trial in a Dutch courtroom. Scott Pelley investigates the evidence and speaks to victims' relatives and prosecutors. Vision of Music – Blind and truly gifted, Matthew Whitaker is wowing audiences all over the world at just 18 years old. Sharyn Alfonsi profiles the emerging jazz pianist who continues to develop his prodigious talent.