If radius of a sphere is rational, then which of the following is/are correct?<br>1. Its surface area is rational.<br>2. Its volume is rational.<br>Select the correct answer using the code given below:

  1. A. 1 only
  2. B. 2 only
  3. C. Both 1 and 2
  4. D. Neither 1 nor 2

Correct Answer: D. Neither 1 nor 2

Explanation

Surface area = 4\pi r^2 and Volume = \frac{4}{3}\pi r^3. Since r is rational, r^2 and r^3 are rational. However, \pi is an irrational number. Multiplying a non-zero rational by an irrational yields an irrational number.

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