Q$9\mathrm{.}2$ My $-$ law.com is a recent start$-$up trying to cater to customers in search of legal services online. Unlike traditional law firms, My$-$law.com allows for extensive interaction between lawyers and customers via telephone and the intemet. In order to allow customers to interact with law firm's lawyers, customers are encouraged to send e$-$mails to my$-$lawyer@My$-$law.com. Emails arrive from $8$ A$.$M$.$ to $6$ P$.$M$.$ at a rate of $10$ emails per hour. At each moment in time there is exactly one lawyer on call, that is$,$ sitting at his or her desk waiting for incoming emais. It takes the lawyer on average $5$ minutes to write the response email. the standard deviation of this is $4$ minutes