1. Use your language to explain the consequences in the following situations. a. What happens to money multiplier if commercial banks choose to hold more reserves than they did before? What happens to total money supply if monetary base is constant? b. What happens to money multiplier and total money supply if people choose to use less cash payment but more digital banking services provided by commercial banks? We assume monetary base is being constant? c. What happens to money multiplier and total money supply in the US when the Federal Reserve started a new large-scale asset purchases (quantitative easing or QE), e.g. buying treasury bills and bonds from commercial banks in 2020? 2. Suppose in one country, its monetary base (B) is $800 billion. The reserve-deposit ratio (rr) is 10%, and the currency-deposit ratio (cr) equals 80%. Then how much is the money multiplier? And how much is total money supply