Longer Questions on the Coronavirus recession

a. April 23, 2020. "(Reuters) - The Federal Reserve's balance sheet increased to a record $6.62 trillion this week as the central bank used its nearly unlimited buying power to soak up assets to keep markets functioning amid an abrupt economic free fall due to the coronavirus pandemic." What is the Fed doing? Is this a good/bad policy?

b."The Commercial Paper Funding Facility II LLC, a special- purpose vehicle set up by the Fed with seed money from the U.S. Treasury, rose to $2.7 billion from $974 million on April 15. That facility began operations last week." Why would the Fed setup this facility? How does this compare to the policy response during the Great Recession?