Select the two correct answers. In what two ways does the author develop the central idea of the passage? 1. The author explains that it is easier to gather information about sound waves. 2. The author gives examples of how sound travels through various substances and surfaces. 3. The author uses light waves to specify how inferior sound waves are at traveling through barriers. 4. The author presents the differences between light and sound waves. 5. The author describes how different surfaces affect the speed of sound.
