$($Highway$)$ While driving home for the holidays, you can't seem to get Little's Law out of your mind. You note that your average speed of travel is about $60$ miles per hour. Moreover, the traffic report from the WXPN traffic chopper states that there is an average of $24$ cars going in your direction on a $1-$quarter mile part of the highway. What is the flow rate of the highway $($going in your direction$)$ in cars per hour? $[2\mathrm{.}3]$

Q$2\mathrm{.}9($Major U$.$S$.$ Retailers$)$ The following table shows financial data for Costco Wholesale and Walmart, two major U$.$S$.$ retailers.

$\backslash$table$[[,$Costoo,Walmart$],[,($$ Millions$),($$ Millions$)],[$Inventories$,$$$,3,643,$$ $29,447],[$Sales $($net$),,48,106,$$ $286,103],[$cogs$,,41,651,$$ $215,493]]$

Source: Compustat, WRDS$.$

Assume that both companies have an average annual holding cost rate of $30$ percent $($i$.$e$.,$ it costs both retailers $$3$ to hold an item that they procured for $$10$ for $1$ entire year$).$

a$.$ How many days, on average, does a product stay in Costco's inventory before it is sold? Assume that stores are operated $365$ days a year. $[L2\mathrm{.}4]$

b$.$ How much lower is$,$ on average, the inventory cost for Costco compared to Walmart of a household cleaner valued at $$5$ COGS? Assume that the unit cost of the household cleaner is the same for both companies and that the price and the inventory turns of an item are independent. $[2\mathrm{.}4]$