Explanation: Marine radar systems typically operate in specific frequency bands, most commonly the X-band and S-band. * **X-band radar** operates at frequencies around 9,000 to 10,000 MHz (9-10 GHz). Using the formula wavelength ($\lambda$) = speed of light (c) / frequency (f), a 10,000 MHz signal has a wavelength of approximately 3 cm. * **S-band radar** operates at frequencies around 3,000 MHz (3 GHz). This corresponds to a wavelength of approximately 10 cm. Therefore, marine radar can be characterized by both its operating frequencies (in MHz or GHz) and its corresponding wavelengths (in cm). Both descriptions are accurate and interchangeable representations of where these systems operate within the RF spectrum.