Consider the following $5$ station system, which has a higher arrival rate to station $5$ due to

necessary re$-$work at that station.

What is the minimum cost, capacity feasible number of machines to install at Station $4?$

Using the same information as above, what is the optimal $($minimum cost$)$ number of

machines to put at station $1$ in order to keep total cycle time under $2\mathrm{.}5$ hours? Assume the

arrival coefficient of variation to station $1$ is $1.$