Reassuring words from the new head of the Fed sent stocks soaring and gave the market its longest winning streak of this year. The Dow jumped nearly 200 as Janet Yellen said she’ll continue the central bank’s low-interest-rate policies. Investors also welcomed news that Congress is poised to raise the US borrowing limit, minus the political drama that happened last year. That would avert the threat of a disastrous default on government debt. The Nasdaq is now in positive territory for 2014; the S&P 500 and Dow are down 1.5% and 3.5%, respectively. The Dow and S&P have risen four straight days, their longest stretch of gains this year.