Question 4(a): What is the variance and standard deviation in monthly cash flow ( under VA '5 old policy), based on Fran's cash flow probabilities? (Warning: If you use the Excel varO or stdeu() functions to do this, you will get the wrong answer. Why?) Question 4(b): What is the variance and standard deviation in monthly cash ow ( under VA '5 old policy), using Pramila's probability distribution for total demand? (Hint: Make another table.)