Communication with submerged submarines via radio waves is difficult because seawater is conductive and absorbs electromagnetic waves. Penetration into the ocean is greater at longer wavelengths, so the United States has radio installations that transmit at \(76 \mathrm{~Hz}\) for submarine communications. What is the approximate wavelength of those extremely low-frequency waves?

A. \(500 \mathrm{~km}\)

B. \(1000 \mathrm{~km}\)

C. \(2000 \mathrm{~km}\)

D. \(4000 \mathrm{~km}\)