If the diameter of a right circular cylinder is 28 cm and its height is 20 cm, then the total surface area is equal to :यदि समवृत्ताकार बेलन का व्यास 28 सेमी है और इसकी ऊँचाई 20 सेमी है, तो कुल पृष्ठीय क्षेत्रफल बराबर है :

1. A1760 cm²1760 सेमी²
2. B1232 cm²1232 सेमी²
3. C1496 cm²1496 सेमी²
4. D2992 cm²2992 सेमी²

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Correct answer: D. 2992 cm²2992 सेमी²

Explanation

r = 28/2 = 14 cm, h = 20 cm. Total surface area = 2πr(r + h) = 2 × (22/7) × 14 × (14 + 20) = 88 × 34 = 2992 cm².r = 28/2 = 14 सेमी, h = 20 सेमी। कुल पृष्ठीय क्षेत्रफल = 2πr(r + h) = 2 × (22/7) × 14 × (14 + 20) = 88 × 34 = 2992 सेमी²।