Using the manual rating model, you have calculated the rate per $1,000 and total premium amount for the Mammoth Mart proposal. You have provided both values to the sales representative. She is surprised by the rate and says it is much higher than it should be. She points out that the rate issued for another group last month, A Management, was also based on the same rate manual but was much lower. The sales representative suggests that your calculation for Mammoth Mart must be wrong. What could explain the discrepancy between the two rates, and how would you address the sales representative's concerns?