Geometry

Question Analysis:
This question asks for the total surface area of a real object — a barrel.
The main focus is correct substitution into total surface area formula.

Key Concept Explanation:
Total Surface Area = 2πr² + 2πrh

Step-by-Step Solution:
r = 7, h = 20
2πr² = 2π × 49 = 98π
2πrh = 2π × 7 × 20 = 280π
Total = 98π + 280π = 378π

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