A level section of highway is to be connected to a section of highway with a -5% grade. The level highway section ends at station 108+40 (elevation 865 ft) and is connect with -5% section of highway at station 139+20 (elevation 758 ft). Using a design speed of 50 mi/h, determine the stations and elevations of PVCs, PVIs, and PVTs of the two vertical curves required to connect the highway segments, as well as the length of the constant grade section (connecting grade is to be as small as possible).