Listen to part of a lecture in a marine biology class.
- What is the lecture mainly about?
- A. Parts of the dolphin’s anatomy that allow it to navigate.
- B. Two different types of communication used by dolphins.
- C. The way that dolphins store air while swimming underwater.
- D. The meanings of different signals used by dolphins.
- Why does the professor discuss the speed at which sound travels?
- A. To describe why sounds made under water can travel long distances.
- B. To show why a person cannot hear a dolphin well when it is under water.
- C. To compare the speed of two different sounds made by dolphins.
- D. To explain how sound waves behave when crossing from one medium into another.
- What is the dolphin’s melon?
- A. An oval-shaped bone that lets the dolphin hear sounds.
- B. An organ made of fat tissue that helps a dolphin send sound waves.
- C. An air-filled cavity that lets the dolphin breathe underwater.
- D. An organ filled with water that helps the dolphin measure depth.
- What is the dolphin’s jaw able to do?
- A. Send rapid clicking sounds into water.
- B. Increase the speed of sounds.
- C. Receive sound waves that have reflected off objects.
- D. Force water through the nasal sacs and out the blowhole.
- How does the professor organize the information in the lecture?
- A. By describing a phenomenon and the physical structures that make it possible.
- B. By describing several of the dolphin’s senses and their relative usefulness.
- C. By contrasting how the dolphin makes two different types of sounds.
- D. By describing an old theory and then a new theory.
- Why does the professor say this: 🎧
- A. To find out whether students are familiar with the lecture topic.
- B. To mention a related topic that will not be discussed in detail.
- C. To mention a common misconception about dolphin vocalizations.
- D. To point out a primary function of dolphin blowholes.
C C AD D D B