$(50$ points$)$ A $3\mathrm{.}2$ miles section of a $4-$lane divided highway includes a $0\mathrm{.}5$ mile

portion on a horizontal curve and $0\mathrm{.}15$ mile spiral at each end of the curve. The

highway has $11$ feet lane width, $4$ feet shoulder width, $30$ feet median, AADT of

$4,000$ and less than $2$ percent up grades.

A$.$ Calculate the predicted total crash frequency of the straight portion

B$.$ Calculate the predicted crash rate for the curve if the radius is $1200$ feet.

C$.$ Calculate the predicted crash frequency for both portions if the lanes are to

be widened to $12$ feet.