Over the next 90 days, economists forecast that the pound may strengthen relative to the dollar by as much as 12%, or it may weaken by as much as 9%. The possible values for the rate of change of the dollarpound spot exchange rate are 9%, 4%, 0%, 5%, and 12%. If these values are equally likely, what are the mean and standard deviation of the future spot exchange rate if the current rate is $1.7/?