Please only answer 10-21 a and b:

10-20. Consider two local banks. Bank A has 100 loans outstanding, each for $1 million, that it expects will be repaid today. Each loan has a 5% probability of default, in which case the bank is not repaid anything. The chance of default is independent across all the loans. Bank B has only one loan of $100 million outstanding, which it also expects will be repaid today. It also has a 5% probability of not being repaid. Explain the difference between the type of risk each bank faces. Which bank faces less risk? Why? 10-21. Using the data in Problem 10-20, calculate a) The expected overall payoff of each bank. b) The standard deviation of the overall payoff of each bank