If the Fed buys 100 million of treasury bonds, how much can bank loans at 5% rr?

In this Fed purchase of $100 Million bonds, Carpenter National Bank (CNB) was one of the banks that sold bonds. In fact CNB sold $1M of bonds. If the required reserve ratio is 5% (rr = 0.05), banks hold no excess reserves, and the non-bank public holds no additional currency how much can CNB loan out? Show all work and explain please.