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Answer:
see explanation
Step-by-step explanation:
Given
T= 2π[tex]\sqrt{\frac{L}{g} }[/tex]
Square both sides
T² = 4π² [tex]\frac{L}{g}[/tex] ( divide both sides by 4π²
[tex]\frac{T^2}{4\pi ^2}[/tex] = [tex]\frac{L}{g}[/tex]
Multiply both sides by g
L = [tex]\frac{gT^2}{4\pi^2 }[/tex]