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A solid is formed by joining a cylinder with two hemispheres of the same radius, one at each end. Which part or parts of the solid are visible on the outside when finding its total surface area? 
AOnly the flat circular bases of the hemispheres
BThe curved surface of the cylinder and the curved surfaces of both hemispheres
CThe total surface area of the cylinder and both hemispheres separately
DOnly the curved surfaces of the hemispheres
Answer & Solution
Correct answer: B. The curved surface of the cylinder and the curved surfaces of both hemispheres
When the hemispheres are attached to the ends of the cylinder, the circular faces where they join become internal. So the exposed area consists of the curved surface of the cylinder and the curved surfaces of the two hemispheres.
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