Answer: 2√2.
- A 2√2
- B 4
- C 2√3
- D 3
Correct answer: A. 2√2
Explanation: Tangent length = √(S₁) = √(25 + 9 − 10 − 12 − 4) = √8 = 2√2.
Three standard 3D solids and their key formulas: a cylinder's volume scales with the full height, a cone's volume is exactly one-third of the cylinder with the same base and height, and a sphere's volume and surface area both follow distinct r-based formulas worth memorising separately.
Concept context
Perimeters, areas, and volumes of 2D and 3D shapes