You don't have to submit the spreadsheet, simply explain your answer in words by what you see$/$understand in MS Excel.

Chapter $12-$ Managing Uncertainty in a Supply Chain: Safety Inventory

Using the Wal$-$Mart Demo for Example $12\mathrm{.}3$ Download Wal$-$Mart Demo for Example $12\mathrm{.}3,$ what happens to the Required Safety Stock inventory when the Desired Customer Service level is increased to $95\%?$ What happens to the Required Safety Stock inventory when the Desired Customer Service level is decreased to $80\%?$ What about $70\%?$ What did you learn from this exercise?

Note: This is not a $$Solver$$ problem. Just change the service level directly in Excel from $\mathrm{.}90$ to $\mathrm{.}80$ and $\mathrm{.}70$ to see the impact on safety inventory.

Using the Wal$-$Mart Demo for Example $12\mathrm{.}13$ Download Wal$-$Mart Demo for Example $12\mathrm{.}13,$ what happens to the Required Safety Stock inventory when the periodic review interval is changed to quarterly, i$.$e$.,12$ weeks versus $4$ weeks? What happens when it is changed to weekly, i$.$e$.,1$ week versus $4$ weeks? What did you learn from this exercise?

Note: This is not a $$Solver$$ problem. Just change the Review Interval directly in Excel from $4$ weeks to $12$ weeks to $1$ week, respectively.