$2-4.$ A six$-$lane urban freeway $($three lanes in each direction$)$ has a free$-$flow speed of $90$ km$/$ h$.$ Traffic includes $10\%$ trucks and $2\%$ express buses. Each truck and express bus displaces $2\mathrm{.}0$ passenger cars from the traffic stream. If the occupancy of passenger cars is $1\mathrm{.}5$ people per vehicle, and buses carry an average of $50$ people per bus, what is the person$-$capacity of the freeway $($in one direction$)?$ It may be assumed that trucks carry one person $($the driver$).$