Step 1: Understanding the Question:
This question tests knowledge of yield regulation formulas.
Step 2: Detailed Explanation:
Von Mantel's formula for yield regulation is Y = 2V/(r-x).
Where Y = yield, V = growing stock, r = rotation age, x = age of final felling.
8V/3r (A): Not von Mantel's formula.
9V/4r (C): Not von Mantel's formula.
2 GS/r (D): Not von Mantel's formula.
Thus, the correct answer is Y = 2V/r-x.
Step 3: Final Answer:
Thus, von Mantel's formula is Y = 2V/r-x, which corresponds to option (B).
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