$16\mathrm{.}19$ Given the data in Problem $16\mathrm{.}18,$ solve the problem except that $($a$)$ the proposal is to divide the

line into three stages, that is$,$ with two storage buffers located between stations $8$ and $9,$ and between

stations $16$ and $17,$ respectively; and $($b$)$ the proposal is to use an asynchronous line with large

storage buffers between every pair of stations on the line; that is a total of $23$ storage buffers.