If L is length of a rail and R is the radius of a curve, the versine h for the curve, is

• A. <img src="/_files/images/civil-engineering/railways/52-17-34-1.png">
• B. <img src="/_files/images/civil-engineering/railways/52-17-34-2.png">
• C. <img src="/_files/images/civil-engineering/railways/52-17-34-3.png">
• D. <img src="/_files/images/civil-engineering/railways/52-17-34-4.png">
• E. <img src="/_files/images/civil-engineering/railways/52-17-34-5.png">