A. (r1 – r2)/ln(r1/r2)
B. (r1 – r2)/ln(r2/r1)
C. (r2 – r1)/ln(r1/r2)
D. (r1 – r2)/-ln(r1/r2)
Correct Answer: A. (r1 – r2)/ln(r1/r2) ✔
Last Updated: March 03, 2019
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