In Country Z, the required reserve ratio is 10 percent. Assume that the central bank buys $50 million in government securities on the open market and that this amount of money is deposited in retail banks.

1. Calculate each of the following.
2. The total change in reserves in the banking system
3. The maximum possible change in the money supply
4. Using a correctly labeled graph of the money market, show the impact of the central bank's bond action on the nominal interest rate.