A freeway in a mountainous recreation area has a $4$ percent upgrade $2\mathrm{.}4$ km long. Base free$-$flow speed is $120$ km$/$h$.$ The traffic stream includes $15$ percent recreational vehicles and $6$ percent trucks and buses. There are two $3\mathrm{.}6$ m lanes in each direction and no lateral obstructions. Interchanges are more than $3\mathrm{.}5$ km apart. PHF is $0\mathrm{.}87.$ Based on past experience, it is determined that the adjustment factor for the character of the traffic stream should be $0\mathrm{.}85.$ What is the maximum hourly volume that can be accommodated at level of service C$?$