Answer: L = 3.6 ft
Step-by-step explanation:
[tex]T=2\pi \bigg\sqrt{\dfrac{L}{32}}\\\\\\\\2.1=2\pi\bigg\sqrt{\dfrac{L}{32}}\\\\\\\dfrac{2.1}{2\pi}=\bigg\sqrt{\dfrac{L}{32}}\\\\\\\\\bigg(\dfrac{2.1}{2\pi}\bigg)^2=\dfrac{L}{32}\\\\\\32\bigg(\dfrac{2.1}{2\pi}\bigg)^2=L\\\\\\\large\boxed{3.5746=L}[/tex]
