Problem $4$: A two$-$lane highway $($two

$12-$ft lanes with negligible shoulders$)$

has a posted speed limit of $50m\frac{i}{h}$

and, on one section, has both

horizontal and vertical curves, as

shown in the figure below. A recent

daytime collision $($a driver traveling

eastbound struck a stationary roadway

object$)$ resulted in a fatality and a

lawsuit alleging that the $50m\frac{i}{h}$

posted speed limit was unsafe speed

for the curves in question and a major

cause of the crash.

$($a$)$ Evaluate the adequacy of the

horizontal sight distance

$($b$)$ Evaluate the adequacy of the roadway horizontal curvature

$($c$)$ Evaluate the adequacy of the vertical curvature

$($d$)$ Comment on the results of your analysis in relation to the design standards