73 A spectrograph is a. typically made from two ordinary pieces of glass. b. a visible-light telescope. c. a device used to measure the intensity of light at each wavelength. d. a radio telescope. e. a device used for clearly resolving physical details of distant objects. 1 points Question 74 The Doppler shift can be used to determine the ________ of an object. a. radial velocity b. three-dimensional velocity c. color d. energy e. temperature 1 points Question 75 The wavelength of a wave is a. the number of peaks that pass per second. b. the distance between one peak value and the next peak. c. the maximum height of the wave above zero. d. the total distance that a wave travels. e. a measure of the wave's velocity