The extension of a circular bar tapering uniformly from diameter d1 at one end to diameter d2 at the other end, and subjected to an axial pull of P is given by

• A. <img src="/_files/images/mechanical-engineering/strength-of-materials/85-27-1.png">
• B. <img src="/_files/images/mechanical-engineering/strength-of-materials/85-27-2.png">
• C. <img src="/_files/images/mechanical-engineering/strength-of-materials/85-27-3.png">
• D. <img src="/_files/images/mechanical-engineering/strength-of-materials/85-27-4.png">