If W is the weight of a vehicle negotiating an upgrade 1 : S along a track having co-efficient of resistance , the tractive force T is given by

• A. <img src="/_files/images/civil-engineering/highway-engineering/28-16-51-1.png">
• B. <img src="/_files/images/civil-engineering/highway-engineering/28-16-51-2.png">
• C. <img src="/_files/images/civil-engineering/highway-engineering/28-16-51-3.png">
• D. <img src="/_files/images/civil-engineering/highway-engineering/28-16-51-4.png">
• E. <img src="/_files/images/civil-engineering/highway-engineering/28-16-51-5.png">