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Determine the surface area of a hollow cylinder with radius 21cm and height 70cm. The calculation seems to be for a closed cylinder though.
ScanSolve AI Answer
Step-by-step solution
4 stepsIdentify the first 2D shape.
The first shape shown is a sector of a circle.
Determine the 3D solid formed by the first shape.
When a sector of a circle is rolled up, its straight edges are joined to form the slant height, and its arc forms the circumference of the base. This creates a cone.
Identify the second 2D shape.
The second shape shown is a part of an annulus (the region between two concentric circles) with a segment removed. It has two curved edges and two straight edges.
Determine the 3D solid formed by the second shape.
When this shape is rolled up, the two straight edges are joined. The inner curved edge forms the circumference of one circular base, and the outer curved edge forms the circumference of the other circular base. This creates a frustum (a cone with its top cut off).
The solids formed are:
- The first shape forms a cone.
- The second shape forms a frustum.
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