The typical monthly home sales by a realtor at Drew County Hometown Realty are calculated to be up to a maximum of 9 new homes sold per month. The probability distribution for a single realtor of selling (x) houses in a month is demonstrated in the chart below. (x) Sales (0) (1) (2) (3) (4) (5) (6) (7) (8) (9) P f (x) 0.05 0.10 0.15 0.20 0.15 0.10 0.10 0.05 0.05 0.05 b. What's the standard deviation for the monthly number of houses sold by a realtor? c. If a realtor sells more houses than the mean plus two standard deviations, they will receive a bonus. To receive a bonus, how many houses must be sold by a realtor per month