A new $2km$ section of a two$-$way multi$-$lane road is to be built in an urban area with the following characteristics:

$2\mathrm{.}5\%$ grade

uphill traffic volume of $2750$ veh $\frac{?}{hr},$

$5\%$ trucks and $2\%$ buses,

$3\mathrm{.}7m$ wide lanes with full shoulders.

How many lanes are required to provide LoS C for the uphill direction? Will the downhill lane requirement be the same? Clearly show your calculation.