The government of Eastlandia uses measures of monetary aggregates similar to those used by the United States, and the central bank of Eastlandia imposes a required reserve ratio of 10%. Given the following information, answer the questions below. Bank deposits at the central bank = $200 million Currency held by public = $150 million Currency in bank vaults = $100 million Checkable bank deposit = $500 million Traveler´s checks = $10 million a) What is M1? b) What is the monetary base? c) Are the commercial banks holding excess reserves?