1. Wavelength: See Summary.        2. Frequency: See Summary.         3. The higher the frequency of a wave, the greater the energy it has.            The shorter the wavelength of a wave, the greater the energy it has.        4. Transverse wave: See Summary.        5. Longitudinal wave: See Summary.        6. Light is a transverse wave: True.           Sound is a longitudinal wave: True.       7. Ultrasound is a longitudinal wave because its vibrations are parallel to its direction.