$3.4$M company has $2$ lathes as the centerpiece of the plant's work. Jobs arrive according to a Poisson process with an average rate of $2$ per day. The processing time of each job has an exponential distribution with an average of $1/4$ day. As the jobs are large, if they are not in process they are stored in a warehouse at some distance from the machine for the next day. However, to save time when bringing them in$,$ the production manager proposes to add space for $2$ work$-$in$-$progress jobs in addition to the one on the lathes. With this proposal, calculate: