$(50$ points$)$ A $3\mathrm{.}0$ miles section of a $2-$lane, $2-$way highway includes a $0\mathrm{.}55$ mile

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

highway has $10$ feet lane width, $5$ feet shoulder width, AADT of $4,000$ and $3\mathrm{.}2$

percent up grade.

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.