equilibrium real interest rate and equilibrium level of saving and investment? Show graphically and explain your result. (6 marks) 7. Explain what will happen to the money supply under each of the following circumstances. Explain your answers. (a) The public decides to increase the amount of currency it holds. (3 marks) (b) Banks decide to hold more excess reserves. (3 marks) Use the quan tity equal this problem. Suppose the money supply is $400. real output is 2.000