To determine the total potential change in the money supply as a result of the Fed's action, we can use the money multiplier formula, which is given by:
\[ \text{Money Multiplier} = \frac{1}{\text{Reserve Requirement}} \]
In this case, the reserve requirement is 20%, or 0.20. So, the money multiplier would be:
\[ \text{Money Multiplier} = \frac{1}{0.20} = 5 \]
Now, since the Fed purchases a $1,000 government bond from you and you deposit the entire amount in your bank, the initial increase in the bank reserves is $1,000. The total potential change in the money supply can be calculated by multiplying the initial deposit by the money multiplier:
\[ \text{Total Potential Change in Money Supply} = \text{Initial Deposit} \times \text{Money Multiplier} \] \[ = 1,000 \times 5 = 5,000 \]
Thus, the total potential change in the money supply as a result of the Fed's action is $5,000.
The correct answer is b. $5,000.