In the case of {HEAD ~ vehicles} which spend a considerable portion of {TAIL ~ their daily road mileage} in dense urban areas in slow moving traffic, such conditions may not be achieved 
In the case of { HEAD ~ vehicles } which spend a considerable portion of { TAIL ~ their daily road mileage } in dense urban areas in slow moving traffic , such conditions may not be achieved
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH