Which of the following statements is accurate? a. amplitude of longitudinal waves is measured at right angles to the direction of the travel of the wave and represents the maximum distance the molecule has moved from its normal position. b. the wavelength of both traverse and longitudinal waves is measured parallel to the direction of the travel of the wave. c. compressions and rarefactions occur throughout a transverse wave. d. sound waves passing through the air will do so as transverse waves, which vibrate vertically and still retain their horizontal positions.