Janet Yellen is heading to Congress. The stakes have never been higher

Janet Yellen, the former chair of the Federal Reserve and President-elect Joe Biden's pick to lead the Treasury Department, faces a huge task ahead.

What's happening: Not only does Yellen have to shepherd efforts to bring the US economy back from its sharpest contraction on record — she must also convince Congress to get on board with Biden's $1.9 trillion stimulus package, as some lawmakers balk at the price tag.