Served

He should ignore the sales data; they are not an appropriate marketing metric.

He should review at least $10$ years of sales data about her stores' performance before making a decision.

He should give each manager a raise, tied to the store results.

He should give bonuses to the managers of Stores $1$ and $2$ and put the Store $3$ manager on probation.

He should seek more information about why the stores had different results before making a decision.