a$.$ What is the average profit per case sold at each of the stores in the data set?

b$.$ Which brand $($Charmin$,$ Dominick's, Kleenex, Northern, Scott$)$ is the market leader based on total number of packages sold? How many packages did this brand sell?

c$.$ In week $383,$ which brand has the lowest total number of packages sold? How many packages did this brand sell?

d$.$ For the "Northern" brand, which week has the highest total number of packages sold? How many packages were sold?

e$.$ Which brand has the lowest total revenue in this data set? What is the total revenue for this brand?