$($a$)$ Determine the minimum length for a crest vertical curve for an urban arterial street where the design speed is $60mph,$ the initial grade is $+2\%$ and the terminal grade is $-1\%.$ Use the AASHTO driver eye and object height recommendations and $1\mathrm{.}0sec$ PIJR time.

$($b$)$ For your design of part a$,$ determine the location and elevation of the PVC and PVT if the PVI station is $455+20\mathrm{.}50,$ and its elevation is $512\mathrm{.}08$ feet.

$[$See example $15\mathrm{.}1$ of Text$]$