Official Guide Explanation:
Data Sufficiency #29




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Solution and Metadata

Question: 29
Page: 275
Difficulty: 5 (Moderate)
Category 1: Geometry > Rectangular Solids and Cylinders > Cylinders
Category 2: Geometry > Rectangular Solids and Cylinders > Surface Area

Explanation: To find the surface area of a cylindrical surface, you need the circumference of the cylinder (to get that, you need radius or diameter) and the height of the surface. Statement (1) offers the height, but nothing about the circumference. Statement (2) is completely irrelevant, giving you nothing about the height of the shaded band or the circumference.

Taken together, they are still insufficient. (1) isn't enough, and (2) contributes nothing. The correct choice is (E).

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