Reuters: Angry U.S. lawmakers hammered BP Chief Executive Tony Hayward at a congressional hearing on Thursday, accusing his company of taking “extreme risks” that triggered the worst oil spill in U.S. history. In his first appearance before Congress since the start of the 59-day-old crisis in the Gulf of Mexico, a tired-looking Hayward sat alone and hunched over the witness table as lawmakers took turns to lambaste the energy giant. “Under your leadership BP has taken the most extreme …