10) You are an analyst at the Treasury Department of a small rural bank in south-east Roxburghshire. You observe the monthly cashflows for the past 20 months. Month 04/20 05/20 06/20 07/20 08/20 09/20 10/20 11/20 12/20 Cashflow 87 -30 59 2 77 -1 58 90 13 Month 01/21 02/21 03/21 04/21 05/21 06/21 07/21 08/21 09/21 10/21 11/21 Cashflow -55 24 99 23 27 -91 -47 30 -29 -89 44 10a) What is the average cashflow over the past 20 months? 10b) What level of cash should the bank maintain in order to have enough cash to withstand a negative outflow with probability 90%? 10c) What level of cash should the bank maintain in order to have enough cash to withstand a negative outflow with probability 95%?