the maximum height, length, and width requirements do not apply to ____, ______, or ____ as long as they are operating during daylight {Ans: auto carriers, trailers hauling poles or pilings, trailers hauling logs}you must stop within___ but not closer than ___ from the a railway crossing {Ans: 50ft, 15ft}the draw bar used to tow another vehicle must not be more than ___ except when transporting objects which can not be easily dismembers like poles, pipes, or machinery {Ans: 15 ft}the maximum width for all vehicles except buses is ___ {Ans: 8 feet}the third step of checking the air brakes is to make sure the parking brake valve closes at ____psi {Ans: 20-40 psi}if the air pressure in the tanks falls below ___, the low air pressure warning will come on. {Ans: 60psi}