Please explain.

Listen Suppose the reserve requirement equals 25 percent. If the Federal Reserve sells bonds worth $100 million, then total deposits in the banking system can be increased by up to $400 million. O True O FalseSuppose the reserve requirement is 10 percent. If an extra $1 billion in reserves is injected into the banking system by the Fed, by how much can total checkable deposits rise? (Assume that the banks keep excess reserves at zero.) a) $1 billion Ob) $10 billion c) $100 million O d) $0.9 billion