$14-1.$A Class I rural two$-$lane highway segment of $20$ miles in rolling terrain has a base free$-$flow speed $($BFFS$)$ of $60m\frac{i}{h}.$ It consists of $12-ft$ lanes, with $4-$ft clear shoulders on each side of the roadway. There are an average of $10$ access points per mile along the segment in question, and $50\%$ of the segment consists of $"$no$-$passing" zones. Current traffic on the facility is $350ve\frac{h}{h}($total$,$ both ways$),$ including $12\%$ trucks and $6\%$ RVs$.$ The directional distribution of traffic is $\frac{60}{40},$ and the PHF is $0\mathrm{.}82.$

$($a$)$ For the current conditions described, at what level of service would the facility be expected to operate? Use a two$-$way analysis.

$($b$)$ If traffic is growing at a rate of $8\%$ per year, how many years will it be before the capacity of this facility is reached?