How will the following actions affect the money supply?
a. a reduction in the discount rate
b. an increase in the reserve requirements
c. purchase by the Fed of $$\$ 100$$ million in U.S. securities from a commercial bank
d. sale by the U.S. Treasury of $$\$ 100$$ million in newly issued bonds to a commercial bank
e. an increase in the discount rate
f. sale by the Fed of $$\$ 200$$ million in U.S. securities to a private investor