A district manager rewards sales teams based on overall sales generated in a month. The data for earnings are shown in the table, where Low represents the lowest sales and High represents the highest sales generated by a single sales team member. Team Low High Range Mean Median IQR σ
Team X 190 2280 2090 1005.9 921.5 841.75 542.7
Team Y 745 1820 1075 1165.5 1147.5 447 262.1
Team Z 950 2275 1325 1906.6 2015.5 362.3 283.6

Part A: If the manager wants to award the sales team that has the most consistent earnings among its team members, which team should it choose and why? Justify your answer mathematically.

Part B: If the manager wants to award the sales team with the highest average earnings, which team should it choose and why? Justify your answer mathematically